Tekie_G7_Main_CBSE_AY24_Final by Uolo

Computer Science

About the Book This book embodies the principles outlined in the National Curriculum Framework (NCF) and the National Education Policy (NEP) 2020. It unveils the world of computer science through a unique and captivating pedagogical approach— seamlessly integrating curriculum content into the mesmerizing adventures of Mel and Conji, fictional figures hailing from the enchanting world of Avora. Our aim is to prepare learners for the dynamic and technology-driven landscape of the 21st century, equipping them with the essential skills they need to thrive in an ever-evolving world.

Special Features • Explore More: QR codes to explore an exciting application of the concept. This element builds curiosity in children and helps them grasp concepts through digital visual aids. 7

• Discuss: Questions to trigger engaging group discussions in the classroom. • Think and Tell: Probing questions to stimulate thinking at an individual level. • Did You Know? Interesting facts related to the application of a concept. • Points to Remember: Chapter end summary. • Do It Yourself: Milestone exercises to practice specific concepts. • Chapter Checkup: A pool of questions catering to all topics and skills covered in the chapter.

About Uolo Uolo partners with K-12 schools to bring technology-based learning programs. We believe pedagogy and technology must come together to deliver scalable learning experiences that generate measurable outcomes. Uolo is trusted by over 10,000 schools across India, South East Asia, and the Middle East.

Singapore

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Gurugram

Bengaluru

hello@uolo.com �550

NEP 2020 based

NCF compliant

Technology powered

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COMPUTER SCIENCE Grade 7

Avora Under Attack

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Foreword

Standing at the forefront of the digital and AI revolution, the importance of coding and computational skills has reached unprecedented heights. In today’s professional landscape, whether it’s in the fields of medicine, space exploration, education, science, or business, no sector remains untouched by this transformative wave. To not just survive but thrive in the 21st century, basic computer literacy is no longer sufficient. Learners must evolve into “digital natives” who can fluently read, write, and communicate in the languages that machines and AI comprehend. Recognizing this imperative, the National Education Policy of 2020 (NEP 2020) has strongly recommended the integration of coding skills, computational thinking, critical analysis, and problem-solving abilities into the curriculum. Moreover, forward-looking subjects like AI, Data Sciences, Computer Applications, and IT have been introduced as elective subjects from grade 9 onwards. It wouldn’t be surprising if further transformative measures are taken even at the elementary education level. Uolo has introduced an innovative 360-degree program for a coding-focused computer science curriculum, known as Tekie, spanning grades 1 to 8. Tekie is a significant stride towards STEM education that aims at making learners future ready—enabling them with skills needed in the ever-changing, technology-driven, and dynamic 21st-century world. Tekie adopts a captivating and engaging approach to learning, in line with the recommendations of the National Curriculum Framework (NCF) 2023 and NEP 2020. The curriculum is ingeniously woven into the thrilling adventures of Mel and Conji, fictional characters from the enchanting land of Avora. The Mel and Conji series epitomizes a modern method of acquiring Computer Science knowledge and honing coding skills and computational thinking. Tekie is a technology-empowered curriculum that encompasses a few key components: • • • •

Main Content Books: These introduce learners to the theory of computer science and the tools used in the field. Topics in AI are also covered, along with experiential and curiosity-based learning resources. Coding Book: Specifically designed to nurture coding skills, this booklet aligns with the experiential and contextual learning approach of the curriculum, fostering critical thinking and problem-solving abilities.

Animated Learning Videos: The program is powered by high-quality animation-based learning videos that deliver learning in an engaging manner. Teacher Manual: This valuable resource supports classroom instruction, ensuring that educators can effectively deliver the curriculum.

Welcome to the captivating realm of Tekie! We hope you relish this educational journey as it equips you with the tools you need to thrive in the exciting and ever-changing world of the 21st century.

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Key Chapter Elements Each chapter has been divided into two key sections. Section A: Story-based Comic In every grade, students embark on an immersive experience in the “Adventures of Mel and Conji”. Within each chapter, in the initial section (Section A), the story unfolds, enveloping learners in an exciting journey. Through the story, students actively connect with fundamental concepts in the realm of Computer Science. Section B: Computer Science Concepts This section of the chapter focuses on the essential academic content. It provides the learning goals and assists teachers in their classroom instruction. This section also includes the following academic assets: QR codes to explore an exciting application of the concept.

HOTS questions to trigger engaging group discussions in the classroom.

This element builds curiosity in children and helps them

Discuss!

grasp concepts through digital visual aids.

How are data redundancy and data inconsistency different from each other?

Explore More!

Computers store data in binary form using electronic switches that can either be on (representing 1) or off (representing 0). This binary storage is the basis of all digital memory.

Interesting facts related to the application of a concept.

Did You Know? Acharya Pingala, a Vedic Scholar, was the inventor of the Binary Number System.

This is the chapter summary. It enables learners to glance through all key concepts covered in the chapter.

Probing questions to stimulate HOTS at individual level.

Think and Tell

Why are we forming groups of 4?

Milestone exercises to practice specific concepts.

A pool of questions catering to all topics and skills covered in the chapter.

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Introduction to Avora

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Places in Avora

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Meet the Characters

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Contents

Number Systems



Introduction to Number Systems



Converting Numbers from One System to Another



Binary Addition



Binary Subtraction

Computer Networks 

Introduction to Computer Networks



Network Terminologies



Network Devices



Types of Computer Networks

Internet Security 

Cybercrime



Cybersecurity

Blockchain

Introduction to Blockchain



Cryptocurrency: A Blockchain Case Study



Problem-Solving



Computational Thinking



Concepts of Computational Thinking



Flowchart

Formulas and Functions 

Understanging Spreadsheets



Applying Formulas



Adding Charts



Working with Data

Database

100



Introduction to Database



Database Management System (DBMS)



MySQL

Animations with Canva 

Designing with Canva



Concept of Layers



Animations

AI—Beyond Reality 

Introduction to AI



Natural Language Processing



The MIT App Inventor

118

141

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Chapter 1 • Number Systems

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Introduction to Number Systems We have learnt about measuring quantities in Science and Maths. We measure length in centimetres, metres, and kilometres. Similarly, we use grams and kilograms to measure weight. But what do we use to measure and express these quantities? We use numbers. But what are numbers made of? They are made of digits—0, 1, 2, 3, 4, 5, 6, 7, 8, and 9. These ten digits together form our Number System. A Number System is a way of representing and expressing numbers using a set of symbols or digits. Different number systems can use different symbols and rules to represent a number in that number system. The base of a number system is the total number of digits the system uses. The number system that we use is the decimal system, also known as the base-10 system. The numbers are expressed using ten different digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9. A question arises here: why do we need to learn about different number systems? The answer is that the different number systems help us understand computers better as computers do not work on the decimal number system. We will later see which other number systems they work on. Furthermore, learning about different number systems helps us to represent data in different number systems. They also help us to convert data represented in number system to another number system.

Types of Number Systems There are four types of number systems that computers understand. Let us learn more about each one.

Binary (Base 2)

Types of Number Systems

Octal (Base 8)

Decimal (Base 10)

Hexadecimal (Base 16)

Decimal Number System The Decimal Number System is the number system that we use every day. The Decimal Number System is a base 10 number system that has combinations of the following 10 digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9. When we deal with a decimal system, we write the base of the number system as the subscript of the number. For example, if we want to write 70, 128, and 349 in a number system notation, we will write: (70)10, (128)10, and (349)10.

Base is 10. Decimal Number System

Digits used: 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9.

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Binary Number System The Binary Number System is a base 2 number system that uses only two digits—0 and 1. A binary number is called a Binary digit or a bit. We express binary numbers as (101)2, (1001)2, (101011)2, and so on.

Base is 2. Binary Number System

Digits used: 0 and 1. The Binary System forms the basis of data storage in computers. In fact, a bit is the fundamental unit of data storage. Different digital devices like calculators, TVs, cell phones, burglar alarms, and watches use this system. But how do these devices understand a bit? Imagine you have a flashlight. It only has two buttons: one to switch it on and the other to switch it off. The state of an “on” flashlight is 1 and the state of an “off” flashlight is 0. If we want to store this information: The first flashlight is on and second one is off. It can be depicted as “10”. This is how these digital devices store information using the Binary Number System.

Explore More!

Did You Know?

Computers store data in binary form using electronic switches that can either be on (representing 1) or off (representing 0). This binary storage is the basis of all digital memory.

Acharya Pingala, a Vedic Scholar, was the inventor of the Binary Number System.

Each number in the decimal number system can be represented in the binary number system as well. This table shows the decimal numbers 0 through 15 in their binary forms: Decimal

Binary

Decimal

Binary

1000

1001

1010

1011

100

1100

101

1101

110

1110

111

1111

Chapter 1 • Number Systems

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Octal Number System The Octal Number System has a base of 8 and has eight digits: 0, 1, 2, 3, 4, 5, 6, and 7. We express numbers in the octal number system as (40)8, (214)8, (376)8, etc.

Base is 8. Octal Number System

Digits used: 0, 1, 2, 3, 4, 5, 6, and 7.

The Octal Number System is widely used in computer applications in the aircraft sector. The octal numbers are used in the form of codes.

Just like in the binary number system, all decimal numbers can be represented in the octal number system as well. This table shows the decimal numbers 0 through 15 and their octal forms: Decimal

Octal

Decimal

Octal

Hexadecimal Number System The Hexadecimal Number System has a base of 16 and has digits from 0 to 9 and letters of the alphabet A to F, where A is 10, B is 11, and so on up to F as 15. We express numbers in this system as (CD)16, (129A)16, (A56)16, etc.

Base is 16. Hexadecimal Number System

Digits used: 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9. Imagine that you have a special way of Letters used: A, B, C, D, E, and F. counting on your fingers. Instead of just using your regular 10 fingers, you have 16 different symbols to count with. The first 10 symbols are just like your regular fingers, and they are represented by the numbers 0 to 9. But this is where it gets interesting: after you’ve counted up to 9 on your regular fingers, you don’t stop. Instead, you start using your special symbols, represented by the letters A, B, C, D, E, and F. These symbols represent the numbers 10, 11, 12, 13, 14, and 15, respectively.

So, when you count with your fingers in hexadecimal, it goes like this: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A (which represents 10), B (which represents 11), C (which represents 12), D (which represents 13), E (which represents 14), F (which represents 15). The Hexadecimal Number System is commonly used in computer programming and in microprocessors. It is used to describe locations in the computer memory. 6

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This table shows the decimal numbers 0 through 15 and their hexadecimal forms. Decimal

Hexadecimal

Decimal

Hexadecimal

Think and Tell

Is the value of 0 and 1 the same in different number systems?

Do It Yourself 1A 1

Identify the systems that these numbers belong to.

a (1010101)2

b (541)8

c (79)10

d (C)16

Converting Numbers from One System to Another A number in one particular number system can be converted into another with some specific rules. Let us learn how to do it.

Decimal to Binary, Octal, and Hexadecimal Let us first learn to convert a decimal number into binary with an example. We will convert (35)10 to its binary form. Step 1: Divide the number repeatedly by two and note down the remainders. See below: 17 2 35 – 34 1 Chapter 1 • Number Systems

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8 2 17 – 16 1

4 28 –8 0

2 24 –4 0

1 2 2 –2 0

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Step 2: Write the remainders in reverse order. The final number with only the 0 and 1 digits is the required number.

Reverse of Remainders 100011

Remainders 110001

So, (35)10  (100011)2. We can also represent the above method in a different way.

Step 1: Create a table and place the number to be converted in the first row.

2 35

Step 2: Write the base of the system, as shown. Here, we want to convert 35 into binary. So, we write 2. Step 3: Now, divide the number by the base of the target system and write the quotient in the next row. Write the remainder in the cell next to it.

÷ Quotient

2 35 17 1

Step 4: Repeat the process till you get a 0 as quotient.

Step 5: Take the remainder from bottom to top. That is the desired binary number. So, we again get (100011)2.

Now, what if we want to convert a decimal number to an octal?

We will repeat the same process. This time the divisor will be 16, because the base for hexadecimal is 16. We will try to write (846)10 in the hexadecimal form. So, (846)10 in hexadecimal is (34E)16.

2 2 2

35 17 8

1 1

2 2 2

35 17 8

1 1

435 54 6

3 6

8 8 8

We will take the same step-by-step approach. This time, we will use 8 as divisor instead of 2. Let us write (435)10 in its octal form. We follow the same approach. So, (435)10 in octal is (663)8. Now, what if we want to convert a decimal number to a hexadecimal?

Remainder

16 16 16

846 52 3

14=E 4

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Do It Yourself 1B 1

Convert (442)10 into binary, octal and hexadecimal.

Any Other Base into Decimal To convert a number in a given base to a decimal, let us use (101011)2 to understand the step-by-step approach. Step 1: Write the number in a row and note the position of the digits from right to left, as shown: Position

Digits

Step 2: Now make a third row and write the values of base to the power of the position. Notice the new row below. Position

Digits

25 = 32

24 = 16

23 = 8

22 = 4

21 = 2

20 = 1

Base power

Step 3: Make a fourth row and write the products of the digits in each place with the base power number. Notice the new row below. Position

Digits

Base power

1 × 32 = 32

0 × 16 = 0

1×8=8

0×4=0

1×2=2

1×1=1

Digit × Base power

Step 4: Find the sum of the numbers found in each place. In this case we get: 32 + 0 + 8 + 0 + 2 + 1 = 43. So, we get (43)10. Now, let us try to convert an Octal into a Decimal. What is the decimal equivalent of (1705)8? We repeat the same process: Position

Digits

83 = 512

82 = 64

81 = 8

80 = 1

1 × 512 = 512

7 × 64 = 448

0×8=0

5×1=5

Base power Digit × Base power We get, 512 + 448 + 0 + 5 = 965. So, (1705)8 is (965)10 in decimal.

Chapter 1 • Number Systems

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Now, let us try to convert a Hexadecimal into a Decimal. What is the decimal equivalent of (1AC7)16? We repeat the same process: Position

Digits

A = 10

C = 12

163 = 4096

162 = 256

161 = 16

160 = 1

1 × 4096 = 4096

10 × 256 = 2560

12 × 16 = 192

7×1=7

Base power Digit × Base power

We get, 4096 + 2560 + 192 + 7 = 6855. So, (1AC7)16 is (6855)10 in decimal.

Do It Yourself 1C 1

Convert the following numbers into the decimal form.

a (1010)2

b (437)8

c (A9C)16

Binary to Octal and Hexadecimal There is a standard method to convert a binary number into its octal or hexadecimal form. Let us see this using an example. We will convert (1110101)2 into its octal form. Step 1: We will group the digits of the binary number. We will form groups of 3, because: Base of octal = 8. Base of binary = 2 and 23 = 8. So, we form groups of 3 starting from the right. If 1 or 2 digits are left, we put them in a new group. See below: Binary Number Grouped Digits

1110101 1

110

101

Step 2: Now, treat each group as a separate binary number and convert into the decimal form. So, we get: Binary Number

1110101

Grouped Digits

110

101

Decimal number from grouped digits

Step 3: We join the decimal numbers formed from the grouped digits. The number formed is the desired number. So, (1110101)2 = (165)8.

Think and Tell Why are we forming groups of 4?

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Now, let us convert (110101011)2 into its hexadecimal form. This time, we form groups of 4 starting from the right. Binary Number

110101011

Grouped Digits

1010

1011

Decimal number from grouped digits

10 (= A in hexadecimal)

11 (= B in hexadecimal)

We get (1AB)16.

So, (110101011)2 = (1AB)16.

Do It Yourself 1D 1

Convert (1001001001)2 into its octal and hexadecimal form.

Hexadecimal and Octal into Binary The method to convert hexadecimal and octal numbers into their binary form is also very similar. We will also use the concept of groups of digits that we learnt in the previous section. Let us use the hexadecimal number (1A7)16 to go through the process. Step 1: We take each digit of the number separately. Hexadecimal Number

A = 10

Step 2: We then convert each digit into its binary form. Hexadecimal Number

Binary form of digits

1010

111

Step 3: Write each derived binary number in groups of 4. Again, we are writing digits in groups of 4 because: Base of hexadecimal = 16. Base of binary = 2 and 24 = 16. So, we get: Hexadecimal Number

Binary form of digits

1010

111

0001

1010

0111

Binary form of digits in groups of 4

Step 4: We now join the different 4-digit binary numbers derived. These final numbers is the desired binary number. We get 000110100111. So, (1A7)16 in the binary form is (000110100111)2 or simply (110100111)2. Chapter 1 • Number Systems

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Do It Yourself 1E 1

Convert the following numbers into binary form.

a (174)8

b (B12)16

Hexadecimal and Octal Conversions Converting hexadecimal numbers into octal numbers, and vice versa, has to be done via other number systems. Let us say we want to convert (721)8 into its hexadecimal form. We first find its decimal form. The decimal form of (721)8 is (465)10. Now, convert this decimal form into the hexadecimal form. The hexadecimal form of (465)10 is (1D1)16. So, the hexadecimal form of (721)8 is (1D1)16. We follow the same steps while converting a hexadecimal number into its octal form.

Do It Yourself 1F 1

Convert the following:

a (764)8 into its hexadecimal form.

(2B1)16 into its octal form.

Binary Addition Binary addition is similar to the addition of decimal numbers. When we add (0)2 and (0)2, we get 0. So, (0)2 + (0)2 = (0)2.

When we add (0)2 and (1)2, we get (1)2. So, (0)2 + (1)2 = (1)2. But what happens when we add (1)2 and (1)2?

(1)2 is basically 1 in decimal as well. So, (1)2 + (1)2 = (2)10 = (10)2.

So, a new place is created and 1 is carried over.

Think and Tell

In a binary system, only 1 can be carried over. In the decimal system, what numbers can be carried over?

We can summarise the rules of binary addition as follows: If we are adding x and y: x

Sum (x + y)

Carry

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So now, we can add bigger binary numbers by this method. For example, let us add (101101)2 and (10110)2.

Carry

So, the sum of (101101)2 and (10110)2 is (1000011)2. 1

Result

Binary Subtraction

Following from the previous section, the rules of binary subtraction are as follows: x

Difference (x – y)

Borrow

For example, let us subtract (11010)2 and (1100)2. So, the subtraction of (11010)2 and (1100)2 is 01110.

Borrow

Result

–

Do It Yourself 1G Add

Subtract

(101101)2 + (111111)2

(1111)2 – (0001)2

(1110001)2 + (1010101)2

(110011)2 – (01010)2

Points to Remember 1

A Number System is a way of representing and expressing numbers using a set of symbols or digits.

Every number can be expressed in different number systems. But the value remains the same.

Base is the number of digits the number system uses. The base of binary is 2, octal is 8, decimal is 10, and hexadecimal is 16.

We use the Decimal Number System in our daily lives.

Binary Number System uses two digits: 0 and 1. Each binary digit is also called a bit.

The Octal Number System is a base-8 number system that uses digits from 0 to 7.

The Hexadecimal Number System has a base of 16. It uses digits from 0 to 9 and letters of the alphabet A to F where A is 10, B is 11, and so on.

We have different rules to convert the number expressed in one number system to another.

Chapter 1 • Number Systems

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Chapter Checkup A. Fill in the Blanks. Hints

bit

numbers

The Binary Number System uses two digits:

The Binary digit is also known as a

The Decimal Number System is a base

In Octal and Hexadecimal Number Systems, we have

When converting binary numbers to their octal form, we put digits together in groups of

and

. number system. and

digits, respectively. .

B. Tick () the Correct Option. 1

Which number system uses only two digits, 0 and 1?

a Decimal 2

The Decimal Number System is also known as the

a Base 2 3

d Hexadecimal

system.

b Base 8

c Base 10

d Base 16

b 9

c 10

d 12

Which number system is used by digital devices like computers and calculators?

a Binary 5

c Octal

What does “A” represent in the Hexadecimal Number System?

a 4

b Binary

b Decimal

c Octal

d Hexadecimal

When converting a binary number into a hexadecimal number, we will form groups of how many digits?

a 1

b 2

c 3

d 4

C. Who Am I? 1

I only understand two digits, 0 and 1. Computers use me to store and process information.

I am used in counting and doing calculations every day. I have 10 digits, starting from 0 to 9.

I am a number system that uses base 8.

I am unique as I let you use letters of the alphabet as my digits too. Programmers love using me.

I am common to all number systems. My value is also the same in all the number systems.

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D. Write T for True and F for False. 1

The Decimal Number System is based on the digits 0 to 10.

In the Hexadecimal Number System, the letter “D” represents the digit 10.

The Binary Number System is the foundation of how computers understand and process information.

Computers can only perform addition, not subtraction.

(D716240234)16 is an octal number.

E. Answer the Following. 1

What is a number system?

What is the base of a number system? Why is it important?

What does the term “hexadecimal” mean in the context of number systems?

Why do we need to convert a decimal number into binary?

F. Apply Your Learning. 1

Convert the following decimal numbers into their octal, hexadecimal, and binary forms.

a (12)10 2

b (110)2

e (906)10

d (111010)2

e (10001001)2

c (717)8

d (B28)16

e (D4E)16

Add the following binary numbers.

b (10101)2 and (1010)2

c (1110101)2 and (110110)2

Subtract the first binary number from the second binary number.

a (11)2 and (110)2

Chapter 1 • Number Systems

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c (100011)2

b (561)8

a (101)2 and (110)2 5

d (671)10

Convert the following numbers into their decimal and binary forms.

a (1B)16 4

c (361)10

Convert the following binary numbers into their decimal, octal, and hexadecimal forms.

a (11)2 3

b (89)10

b (1010)2 and (10101)2

c (110110)2 and (1110101)2

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Chapter 2 • Computer Networks

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Introduction to Computer Networks Suppose you are going on a family road trip. Think about how roads connect different places, like villages, cities, and towns. In a similar way, our world is linked through computer networks. Just like you talk to your friend on the phone and share messages with him, computers use networks to share information. These networks are like digital roads that help messages and data travel between devices, irrespective of their location.

In simpler terms, a computer network is a way to connect computers using communication devices so that they can exchange data and resources with each other.

Uses of Computer Networks Computer networks are used for different purposes in our daily lives. Here are some of the uses: File sharing: With the use of computers, users can share their data and documents with each other. For example, you can share any file with your friend, who is located remotely in a different country. Resource sharing: Suppose all the students in your class are in the Computer Lab, each using an individual computer. The teacher has asked all the students to print an article on the topic “Importance of communication in our lives”. Will you want a separate printer for every computer? The answer is: No! You can observe that only one printer in the lab will be shared with all the students, and this is possible only because of the computer network. This is called resource sharing. Communication: Suppose your teacher has assigned a project to you with two other team members. One of your team members has gone to some other city for a week. You can then connect with your team member using a computer network and can complete the project on time. This is possible with the help of computer networks only.

Chapter 2 • Computer Networks

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Database access: Computer networks help in accessing the same database from multiple computers. This further enhances the storage capacity of data. It also gives us access to the stored data.

Security: Suppose you have stored your class assignments on the network. Your data is secured on the network, because a network key (password) is provided to the user to access that data.

Backup: What if you accidentally delete your project files from your individual computer in the network? Do not worry! In computer networks, the data is stored on a central computer, known as the server. The server keeps a backup file of everything that we store in it. So, backing up data is also a benefit of computer networks. In case of data loss, you will have the backup copy of your data.

Think and Tell

Is sharing a file through a pen drive an example of using computer networks? Why/Why not?

Advantages of Computer Networks Computer networks are beneficial to us in many ways. Some of the advantages of computer networks are discussed as follows: Cost reduction: Because the hardware resources (printers and scanners) are shared among all the computers on the network, the cost of additional equipment is saved. Less data redundancy: Data redundancy occurs when the same piece of data exists in multiple places. All the data in the computer network is stored on the server. Therefore, there is less data redundancy in the network. Less data inconsistency: Data inconsistency occurs when same data exists in different formats at different places. Since data redundancy is reduced due to computer networks, data inconsistency is also reduced.

Discuss!

How are data redundancy and data inconsistency different from each other?

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Data centralisation: In a computer network, the server provides services to all the other computers. All the data in a computer network is stored on a server at a centralised location. This centralised storage of data provides easy accessibility to all users. Data recovery: The server’s capability of taking regular data backups helps in easy data recovery in case of data loss or network failure.

Think and Tell

How can computer networks be useful to an organisation?

Disadvantages of Computer Networks Apart from many advantages, there are some disadvantages of computer networks also. Let us learn about them. Security concerns: Network security is a major concern as the data, which is being shared on a wired and wireless mediums, can be stolen by some tricky people, leading to data loss or change of data. High maintenance cost: Just think that sometimes your gadgets need some fixing and cleaning for smooth functioning. Likewise, a computer network also needs timely maintenance by a special team of experts. The maintenance cost of a computer network is higher than that of an individual computer. Purchasing the necessary equipment (such as cables and other devices) for network architecture can be expensive. Complex architecture: Computer networks have complex architecture, for which a specific type of setup is required. This setup involves arranging and connecting various hardware and software components in a precise way to ensure effective communication and data exchange among devices.

Compatibility issues (hardware and software): To be a part of a network, you should have the same version of hardware and software similar to all the other computers, which are supposed to be a part of the network.

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Data loss (in case of network failure): If the server computer that stores all the data of individual computers fails, what will happen then? All the data will be lost. This is a major disadvantage of a computer network.

Need for skilled personnel: Managing a large network is complicated. It requires training and usually, a network manager needs to be employed. To maintain a large network, a special team of skilled technical persons is also required. Hence, this also becomes expensive.

Do It Yourself 2A 1

Which of the following is not an advantage of computer network?

a Communication

b File Sharing

c Backup of Data

d Network Maintenance

Your computer teacher has assigned a project to Sneha and Priyanka. Due to some emergency, Priyanka has to leave her station. How will they complete their project together, and on time?

Suppose there is only one scanner in your computer lab at school. All the subject teachers want to scan their documents while sitting at their own computers in the computer lab. Will they be able to work with one scanner or will they need a separate scanner for every computer?

Network Terminologies Some important network terms are discussed below: Term

Meaning

Node

A device in a computer network that is used to send or receive data, like a computer, mobile, tablet, laptop, etc. Such a device is called a node.

Link

It is a connection between two computers or devices, such as a cable, Wi-Fi, fibre optic, etc.

Packet

A unit of data or information that is transferred over the internet. For example, you send an e-mail or message to a friend.

Protocol

This refers to a set of rules that are to be followed for sending data over a network.

Topology

Physical arrangement of computers or devices to link with each other, for example, star topology, bus topology, etc.

Bandwidth

The amount of data or information that can be transmitted over the internet or a network. For example, 1 Gbps or 1 Mbps (bps—bits per second, G stand for Giga, and M for Mega).

Latency

The time required for a message to travel from one network endpoint to the opposite endpoint.

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Think and Tell

What is the maximum capacity of data transfer nowadays?

Explore More!

Data units start from 1 bit and can go up to yottabytes. Find out about it here!

Network Devices Computer network devices are hardware components that are required for the computers to communicate with one another over the network. Some of these are discussed as follows: Hub: It is a networking device that transmits the received information to all the devices on the network. A hub has many ports in it. A computer that intends to be connected to the network is plugged into one of these ports. Switch: A switch is a device that connects different computers on a network. It transfers data from one computer to another. A switch receives data from one computer, processes that data, and forwards that data to the destination device. Router: It is a device which gives access to the data or information over a network. Routers may also be used to connect two or more logical groups of computer devices known as subnets or subnetworks. A Router needs an IP address of a computer to which the data is to be sent. IP address is a unique numerical identifier. Each device on the network has an IP address. Bridge: A bridge is a device that acts like a ‘gate’ between two networks. It is used to exchange information between two networks that use the same communication protocol. A bridge also acts like a filter that checks the incoming information and transmits that information only if required.

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Repeater: It is a networking hardware device that regenerates the incoming signal before forwarding it to the destination. The repeater helps regenerate weakened or distorted signals.

Gateway: It is used to exchange information between two networks that use different communication protocols. Gateway acts like an entry and exit point between two networks. Every piece of data has to pass through the gateway before being transmitted to another network.

Do It Yourself 2B 1

is a device that connects two networks which are using different protocols.

Each device on the network has an

Name different computer network devices.

address.

Types of Computer Networks There are different types of networks, which are categorised according to their geographical areas and topologies. Let us discuss both types one by one.

Types of Networks Based on Area Types of Computer Network

PAN

LAN

MAN

WAN

Personal Area Network (PAN): A PAN, which is the most fundamental kind of network, is made up of a wireless modem, one or two PCs, smartphones, tablets, printers, etc., working within a range of 10 metres (33 feet). These networks are usually controlled by a single person or business from a single device, and they are generally found in small-scale workplaces or houses. They can be categorised into wired and wireless, based on the type of connectivity among the networking devices. 26

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Local Area Network (LAN): It is a computer network that only extends up to a few metres across a relatively limited region, such as a school or a college building. LANs are commonly used to link desktop computers and workstations in corporate settings to share resources. LAN ranges between 100–1000 metres.

MAN

Metropolitan Area Network (MAN): It is a computer network that connects devices within a metropolitan city or a small town. Two or more connecting LANs form a MAN. MAN ranges up to an area of 100 km. MAN is costlier than LAN. The cable TV network is an example of a MAN.

Wide Area Network (WAN): Wide Area Network connects the computers from various countries and continents. WAN connects different LANs and MANs from all across the globe. The internet is an example of WAN.

Wireless Network: A wireless network can be created in a small area, such as a room or a house. The technology used to create a wireless network is known as Wi-Fi. Wi-Fi stands for Wireless Fidelity. It is a type of local area network (LAN) that uses wireless communication technology to connect various devices, like computers, smartphones, tablets, and other gadgets to the internet using a Wi-Fi router. These devices can also be connected to each other without the need for physical cables.

Think and Tell

Which type of network will you recommend in your school to share hardware devices?

Types of Networks Based on Topology Topology is a physical and logical layout of different devices (nodes) and connections in a network. The configuration of how computer systems or network devices are connected to one another is known as a topology. Different types of network topologies are discussed as follows: Bus Topology: In a bus topology, all the nodes are connected to a single common cable. A node puts a message on the cable, which is sent to all other nodes in a network. The disadvantage of it is that the message clashes when multiple nodes try to send data at the same time. The terminator removes data from the line.

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Star Topology: In star topology, the nodes are connected to a centralised hub, switch, or computer forming a star. The central computer is called the server, while other computers are called the clients. The disadvantage of the star topology is that if the central computer fails, the whole network will be disabled. Ring Topology: In ring topology, the nodes are connected to each other forming a ring. A node forwards the message received to it from the previous node to the following node. Data flows unidirectional in a clockwise direction. The disadvantage of it is that it if any one node fails, the entire network will fail.

Tree Topology: In tree topology, nodes are connected in a parent-child hierarchical manner. Tree topology is a combination of star and bus topology. The disadvantage of this topology is that the entire communication depends upon the bus, and if the bus fails, the entire network will fail.

Mesh Topology: In mesh topology, every node is directly connected to every other node forming a mesh. The disadvantage of mesh topology is that the network is costly due to the large number of cables used and the difficulty in finding the faulty node. An example of mesh topology is the internet.

Discuss!

How is a tree topology better than a ring topology?

Points to Remember 1

A computer network is a way to connect computers using communication devices so that they can exchange data and resources with one another.

Computer networks have many uses, such as file sharing, communication, database access, data backup, etc.

There are many advantages of computer networks like data centralisation, data consistency, less data redundancy, and cost reduction.

There are many disadvantages of computer networks, like network failure, stealing of data, maintenance cost, and complex architecture.

Computer networks are of many types: PAN, LAN, MAN, WAN, and wireless network.

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There are different network devices such as a hub, switch, router, repeater, bridge, and gateway.

Different topologies of computer networks are: bus, star, ring, tree, and mesh topology.

Chapter Checkup A. Fill in the Blanks. Hints 1

computer network

share resources.

mesh

inconsistency

MAN

repeater

is a group of two or more computers connected to exchange information/data and to helps to regenerate weakened or distorted signals.

In a

topology, all the nodes are connected to a single common cable.

In a

topology, every node is connected directly to every other node.

5 6

bus

connects devices within a city or a small town. means the same data exists in different formats at different places.

Data

B. Tick () the Correct Option. 1

Which of the following is not an advantage of a computer network:

a Cost Reduction 2

Data

d Less data inconsistency

c Software, Connections

b Differentiation

and to

d Hardware, Communication lines

c Consistency

d Redundancy

c Mesh

d Ring

c Router

d Gateway

Which of the following is not a network topology?

a LAN 5

b Devices, Secrets

occurs when the same piece of data exists at multiple places.

a Inconsistency 4

c High maintenance cost

A computer network is a group of two or more computers connected together to exchange share .

a Data, Resources 3

b Less data redundancy

a Hub

b Star routes the data on a network.

b Switch

C. Write T for True and F for False. 1

MAN is costlier than LAN.

PAN connects people across the globe.

Hub uses only a single port.

No data recovery is possible in case of computer networks communication.

There is no single point of failure in case of Mesh Topology.

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D. Answer the Following. 1

Define the term computer network.

Write the advantages of a computer network.

Explain the terms hub and repeater.

Discuss star topology and state one disadvantage of it.

Differentiate between bus and ring topologies.

E. Apply Your Learning. 1

Ms. Anju wants to open her new office branch in Pune and wants to connect with previously opened branches in Haryana and Mumbai. Which network type will she prefer?

You are talking to your friend on a network, and you observe that after some time your signal weakens. Which network device will you need to improve the signal strength?

In a household, wireless networks (Wi-Fi) are commonly used. Describe the advantages of having a wireless network at home as compared to a wired network.

Arun is the technology officer in an organisation. What three potential disadvantages or challenges might he face when managing a computer network?

Imagine your mother is a businesswoman. Why do you think it’s a good idea for her to connect all the computers in her company together?

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Chapter 2 • Computer Networks

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Chapter 3 • Internet Security

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Chapter 3 • Internet Security

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Cybercrime When we talk about technology, the first thing which comes to our minds is the internet. The internet has brought the world closer. It has changed our lives. But nothing is perfect because just like in the real world, the world of the internet also has its share of crime, called cybercrime. The word cyber means internet-related, and crime is something that is illegal. Therefore, cybercrime means crimes that happen on the internet. Cybercrime is considered a serious offence as it can harm many users of the internet across the world. Some examples of cybercrime are: • using the internet to steal another user’s personal information; • breaking into, or hacking, websites and accounts; • infecting other computers by creating or sending viruses; and • bullying others on social media platforms. Awareness of the different kinds of cybercrime helps us avoid them.

Categories of Cybercrime Cybercrime can be classified into different categories based on the nature of the criminal activity.

Cybercrimes Against Individuals These crimes include the theft of personal information, such as credit card numbers, Aadhaar card numbers, and passwords. Here are a few kinds of cybercrimes committed against individuals. Awareness about the different kinds of cybercrime helps us avoid them. 1. Phishing: It is the attempt to trick a user to get his or her personal information. This is generally done through fake emails. The stolen information can be used for: a. Spoofing, or identity theft: where the criminal will pretend to be someone else on the internet to fool and steal more information from other users. b. Scamming: where the criminal will send believable-looking emails or advertisements to steal banking information and money from the users. 2. Cyberbullying: Targeting a user on social media and emotionally harming him or her by: a. creating fake accounts of that user; or

HATE

LOSER @%?#!!!!

UGLY

STUPID

b. spreading lies, incorrect information or rumours about that user; or 36

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c. shaming or abusing that user for his or her views. d. extortion, or forceful taking of money by blackmailing or harassing a user, sometimes after stealing his or her personal information. 3. Cyberstalking: Using the internet to follow another user’s location, monitoring his or her actions, and harming that person’s privacy.

IzE!

ClAiM Pr

Did You Know?

When a website’s URL starts with ‘https://’ instead of just ‘http://’, it is more secure.

Cybercrimes Against Businesses These crimes involve the theft of intellectual property, such as trade secrets, sensitive information, and ownership of an invention or idea. These crimes can be of the following types: 1. Corporate Espionage: Espionage means to spy or secretly monitor a person, company, or a government without their knowledge. Corporate means of or relating to offices or businesses. Therefore, corporate espionage is the illegal spying on a business or office to steal their information. This can be done through hacking, or gaining access to a person or organisation’s computer or computer network in order to spread viruses or steal information. 2. Denial of Services: Purposely flooding the office or business’s computer or network with so much data transfer, or traffic, that it becomes slow, creates network downtime or stops working altogether.

Acc De ess nie d

Network downtime is the inability of a network to function as a result of a specific system or an application failure. This disturbs the normal functioning of an office or a business, thereby disrupting work.

Cybercrimes Against Governments These crimes involve the theft of sensitive data of a country’s government such as information about their military, policing, economy, tax, and citizens. They can also involve cyberwarfare, which is the use of cyber attacks to disrupt or disable government systems. 1. Ransomware Attack: In these, hackers encrypt government systems and demand a price to provide the decryption, possibly causing huge disturbance in government operations.

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2. Insider Attack: An insider attack is a cybersecurity threat that comes from employees or contractors within government offices who may intentionally or unintentionally leak important information and use that information to commit cybercrimes.

Think and Tell

If a hacker locks your friends files in his computer and demands money to unlock them, what kind of cyber threat is that?

Cybercrimes Against Society The internet can also be used to create a negative impact on the general public or various social groups. These crimes often exploit the interconnected nature of the digital world to cause harm, spread fear, or disrupt the functioning of society. 1. Cyberterrorism is the use of computers and the internet to attack or frighten large numbers of people. 2. Spreading Fake News: Spreading fake news is the spreading of false or misleading information presented as actual news with the intent to manipulate public opinion, leading to confusion and discord in society. It can be shared on social media, websites, messaging apps, and even traditional media outlets.

Did You Know? In 1961, MIT Professor Fernando Corbato invented the first digital password for secure access to a giant time-sharing computer.

Think and Tell

Share some tips you can give your friends on staying safe while using public Wi-Fi networks.

Do It Yourself 3A 1

What is cybercrime, and how is it different from real-world crime?

What are the different kinds of cybercrimes? Briefly define them and provide an example of each.

Read the strips and identify the cybercrime.

a I got an email which has a message that my account will expire soon…

Type of Crime:

I have to fill in this form. They are asking for my bank account number and address.

I got low grades in Mathematics. One of my classmates is calling me loser on social media.

He has even tagged me in one of the posts, calling me bad names.

Type of Crime:

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Match the Columns. Column A

Column B

Cybercrime

Tricking a user to steal his personal information.

Corporate Espionage

Stealing government information and demanding money for its return.

Ransomware attack

The act of breaking the law using the internet.

Phishing

Illegally spying in a business.

Cybersecurity Just as you lock your doors and windows to keep thieves out of your house, cybersecurity serves as a lock for your computer and the internet. Cybersecurity functions like a digital shield, ensuring that your computer and personal information remain safe and secure from threats on the internet. It is all about safeguarding your online activities from harmful users and hackers. Cybersecurity is the practice of protecting computers, systems, and networks from digital attacks.

How to Implement Cybersecurity Here are a few ways that can help you protect your computer better.

Strong Password A password is like having a secret code that only you know and that can keep your online accounts safe from hackers. A strong password guards your computer and information like a fortress can guard a city. To create a strong password, use the following tips: 1. Have at least 12 characters in your password.

2. Use a combination of symbols, numbers, and capital and small letters.

3. Avoid passwords that can be easily guessed, like your nickname, your phone number, or your date of birth. 4. Change your password frequently.

Multi-Factor Authentication (MFA) MFA is like having a double or even a triple lock on your online accounts. MFA makes your account extra secure by adding more layers of verification.

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Avoid Suspicious Links and Emails You must have seen some emails or links saying things like “Your account will be deleted” or “You won a prize; click here now!”. Take a deep breath and don’t rush to click on it. Never click on these types of links or emails. Simply delete it instead and inform your parents or your teachers about it.

Install and Maintain Antivirus Software To keep your personal information on your computer, you can install antivirus software which saves your computer from viruses before they can harm your computer. Some popular antivirus software are McAfee, Quick Heal and Norton.

Use Secure Networks and Browsers Always be cautious of the website you are visiting. Securing your browser by changing its setting to filter out harmful links and sites can make your net surfing enjoyable and safe. Our computers also have a firewall. A firewall is a network security device that monitors and controls incoming and outgoing data in the network. The main function of a firewall is to filter and block harmful content when you are using the internet.

Explore More!

Hacking is not always bad. Ethical hacking helps to keep the online world safe. Know more about it here!

Do It Yourself 3B Read the paragraph and answer the following questions. As time goes by, families sometimes move to different cities. We can stay in touch with them even if they’re far away using the internet. We can also make new friends online, but we need to be careful. Not everyone online is who they say they are. Since we can’t see them in real life, it’s best not to share personal things like our name, where we live, or our phone number with them. Some people might want to make us uncomfortable or trick us, so it’s important to let the elders we trust know if something feels strange. We should never share passwords of our online accounts with anyone. A strong password has a mix of letters, numbers, and special characters. Also, it’s a good idea to have different passwords for different things. If one gets compromised, the others will still be safe. By being cautious and using the Internet responsibly, we can have fun and stay safe at the same time. Questions:

What’s an important thing to remember when making new friends online? Why?

Why is it risky to share personal information like your name, address, or phone number with people you meet on the Internet?

If something feels strange while you’re using the Internet, what should you do?

Why is it a bad idea to share your online account passwords with anyone, even your friends?

Imagine you met someone online who was really nice, but he started asking for your personal information. What should you do in that situation?

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Points to Remember 1

The internet has changed our lives but also brought in cybercrime.

Cybercrime involves harmful actions done through computers, like stealing information or bullying online.

Cybercrimes against individuals involve the theft of personal information, such as credit card numbers, and passwords.

Crimes against businesses involve stealing intellectual property, hacking, denial-of-service attacks, and data theft.

Crimes against governments include theft of sensitive government data.

Crimes against society involve spreading fake news and cyber terrorism.

To protect ourselves from cybercrime, we need to follow good cybersecurity practices.

Using strong passwords, enabling multi-factor authentication, avoiding suspicious links, installing antivirus software, and using secure networks are some ways to stay safe online.

Cybersecurity is essential to protect ourselves from online threats and enjoy a safer internet experience.

Chapter Checkup A. Fill in the Blanks. Hints

cyberbullying

e-mail spoofing

password

antivirus

Cybercrime is a wrong or harmful action done through

Cybercrimes against individuals can involve the theft of personal information like

3 4 5

digital devices . .

is when an attacker sends an email with a fake sender address to deceive the recipient. messages.

involves using digital platforms to harm others through aggressive and hurtful

Installing and maintaining

on your computer can help protect it from viruses.

B. Tick () the Correct Option. 1

What should you do if you encounter cyberbullying?

a Ignore it and don’t tell anyone

b Stand up to the bully and respond

c Report it to a trusted adult and seek help

d Get worried and panic

What is the goal of cyberterrorism?

a To bring peace and harmony to society

b To create fear, panic, and disturbance

c To cause direct physical harm or casualties.

d To improve cybersecurity

Chapter 3 • Internet Security

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with hurtful messages

using technology and the internet

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How can you protect your online accounts?

a Use weak and simple passwords

b Avoid using Multi Factor Authentication (MFA)

c Create strong passwords and enable MFA

d Share your passwords only with your close friends

What can antivirus software do for your computer?

a Provide entertainment and games

b Protect against viruses and malware

c Increase computer speed and performance

d Help to play games easily

What is the purpose of MFA in cybersecurity?

a To block access to all websites

b To help hackers steal your data

c To slow down internet connection speed

d To make your computer more secure by providing additional passwords

C. Who Am I? 1

I am a cybersecurity threat that comes from someone within the organisation who has authorised access to its resources and can carry out harmful actions.

I am a cybercrime aimed at tricking people into giving away personal information or money.

I am a network security device that monitors and controls incoming and outgoing data in the network.

I am a strong code that only you know and can keep your online accounts safe from hackers.

I am a cybercrime that hackers use to encrypt organisational systems and demand a price to provide the decryption.

D. Write T for True and F for False. 1

Multi Factor Authentication (MFA) adds extra security to online accounts.

It is safe to click on any links or download files from unknown sources.

Email spoofing is a safe and harmless activity.

Ransom attacks involve stealing sensitive government data.

E. Answer the Following. 1

What are the risks of using public Wi-Fi networks, and why should you be careful?

What is cybersecurity and why is it important?

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What is cyber stalking and why is it important to report such behaviour?

What is multi-factor authentication (MFA), and why is it a good practice?

What is identity theft and why is it important to protect your personal information online?

F. Apply Your Learning. 1

Pranav receives an email from a bank asking him to verify his account details urgently. The email looks official, but something seems suspicious. What do you think: is this an attempted cybersecurity breach, and if it is then what type of security breach is it?

Raman is at a coffee shop with free Wi-Fi and wants to check his social media accounts. What do you think, should he connect with the coffee shop’s Wi-Fi and start working on his project or should he not connect with the Wi-Fi ? If your answer is no, explain why.

Geeta has created a new online account and needs to set up a password. What are the essential elements of a strong password?

Malin comes across a website that promotes illegal activities and harmful content. Should he open that website on his system?

Ritu receives an email claiming that she has won a big prize and needs to click on a link to claim it. The email looks convincing, but something feels off. What should she do?

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Chapter 4 • Blockchain

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Introduction to Blockchain Imagine you went on a school trip. You and your friends decided to create a digital diary. You wanted to store and save the memories of this trip in the drive.

In this diary, you all wrote down all the things that you did together, and everyone in the group has a copy. Whenever you or your friends added anything new to the diary, like a special memory or an important event, everyone of you had to agree if it was true and accurate. The digital technology named Blockchain works in a similar way. To understand Blockchain in a better way imagine that you and your friends were using computers to note down your memories. Each time a new memory was entered, it was like adding a new page to this digital diary. But here is the interesting part: every new page is linked to the one before it, just like a series of dots that are connected. Each page can be considered a block. Thus, a chain of connected pages is a blockchain. Since everyone of you can see the whole chain, it’s really hard for anyone else to sneak in and change something without everyone noticing it. The blockchain helps computers keep important information safe by connecting the pieces together in a way that’s really hard to cheat.

Discuss!

What would happen if one or two individuals of the group could add details in this diary that were not accurate?

Chapter 4 • Blockchain

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Features of Blockchain Blockchains have the following features: Decentralisation Here, decentralisation means that there is not just one single person, organisation, or central authority in control of it. Instead, control or decision-making is spread out among many different individuals or entities. A blockchain is a digital chain that may be made up of many blocks from many parties involved. It allows people to store and share information in a decentralised and distributed system. Security and Immutability A block is a specific unit of data that is part of a blockchain that holds specific verified information. The whole process is designed to be immutable, which means that while the information in it can be seen by all the users, no one will be able to change or delete the information. Transparency Transparency, here, means that everyone who is a part of that blockchain can see all the information, and nothing is kept hidden from them. This helps to build trust among the users. User Privacy and Security Blockchain also keeps the personal details of the users safe. This means that while everyone gets to see the information in that blockchain, no user can see each other’s personal information.

Did You Know? Blockchain technology came into existence in 2008. However, the identity of the person or group behind the creation remains a mystery. The pseudonym “Satoshi Nakamoto” is used as the inventor, but the real identity of this individual or group has never been found.

Working of Blockchains Let us understand how Blockchains actually work. Imagine that you want to buy a piece of artwork from an online seller. What would the entire process look like if it were operating through Blockchains? Let us see!

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Blockchain confirms availability of artwork with seller

Buyer and seller connect

1 Buyer sends the purchase request

All before, during and after details of the purchase available on the blockchain

Artwork physically transported to buyer, information confirmed and updated on blockchain

Blockchain records transfer of money from buyer. Information confirmed by bank.

Blockchain records accurate purchase agreement that both parties confirm

1. You, as the buyer, get accurate information on the blockchain on whether the artwork you are interested in is actually available with the seller or not. The security and transparency in blockchains allow us to trust the information and the seller. 2. You contact the seller to buy the artwork. 3. You then send a request to the seller that you want to buy the artwork. This request ‘transaction’ is recorded in the form of a block on the blockchain. Remember that each piece of new information is stored as a block in the blockchain. So, both you and the seller will be able to ‘see’ the updated information. 4. The seller reviews your offer, and you mutually agree on the terms of the transaction. Once both parties have agreed, this information will be recorded as a block on the blockchain. Both of you will be able to access this information anytime you want, but neither of you will be able to change it.

Think and Tell

What information is so important on the agreement that the blockchain should not allow any party to change it?

5. After that you make the payment. Once the bank confirms that the money has been deposited into the bank account, this information of making the payment is also safely recorded on the blockchain. Since this information cannot be changed, your money is secured. 6. The seller sends the artwork to you, and you receive it after some time. This information is also updated into the blockchain. 7. Once you receive the artwork, you update the information that the transaction is now complete.

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8. In case the seller refuses to send the goods even after receiving the money, the entire transaction details are available as proof that the artwork was not sent to you even after you had paid for it. Once again, the blockchain system can save you from losing your money. 9. At the end of the entire transaction, the blockchain now holds all details. It also knows that the seller no longer has that particular artwork, and that you now possess it. It is important to note that the above example is a visualisation of how the purchase of artwork could work through blockchain. All digital transactions around us do not work on blockchains today.

Explore More!

Blockchain is a technology that can be applied in many fields! See some surprising uses!

Challenges of Blockchain Like all other technologies, blockchain has some challenges too. Let us look at some of them. Long Validation Process One of the biggest strengths of blockchain is that it can provide accurate information. But the process of validation itself is sometimes very cumbersome! Slow Speed in Working with Large Amounts of Information The blockchain records all developments as information. But what if there are too many transactions that involve several people? Maintaining verified information at each step would become very difficult. So, while working on a larger scale, maintaining speed with security is difficult. Interoperability We learnt that blockchains are decentralised. It is possible that different blockchains are fundamentally different in the way they have been designed and created. This sometimes makes it difficult for different blockchains to communicate with one another. Legal Challenges Technology brings users from across the world together! But citizens of different countries are bound by the laws of their respective countries. Laws related to IT and technology tend to vary from country to country. So legal situations while dealing with blockchains might be complicated.

Do It Yourself 4A 1

Tick () the correct answer. What is a blockchain?

a A type of physical network

b A digital puzzle

c A decentralised digital book of records

d A type of computer

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Write T for True and F for False.

a A blockchain is controlled by a single central authority. b Different blockchains may be different. c Different countries have almost the same laws related to blockchain. d The information stored in blocks can easily be accessed by anyone who has access to the blockchain. 3

Imagine your school starts using blockchain for the entire exam process. Thus, there will be different blocks for creating question papers, conducting exams, and announcing results. Will you be able to change your marks in the system without the teacher knowing? Why/Why not?

Cryptocurrency: A Blockchain Case Study We use the Indian Rupee, or INR, to buy things in India. The INR is the national currency of our country. Similarly, other countries have other currencies. We use Dollars, Euros and Pounds in the US, Europe and the UK, respectively. When we withdraw money from the bank to buy something, the bank stores the records of our account. It can, at any time, tell us how much money is left in our account. What if we use a debit card or UPI to pay? The bank digitally certifies that we have the money and lets us make the purchase. Once the purchase is made, the money immediately gets debited from our bank account. Cryptocurrencies are very different from our usual currencies. Cryptocurrency is a purely digital or virtual currency that can also work as a medium of exchange. But, it exists only in digital form and doesn’t have physical coins or banknotes. Bitcoin is the name of a famous Cryptocurrency. Unlike traditional currencies, Cryptocurrencies do not have a banking system that records transactions. So how do they work? Cryptocurrencies work on blockchain. Let us learn how.

How Does Cryptocurrency Work on the Blockchain? In usual currencies, the bank is the figure of authority that allows or disallows a transaction. The following infographic shows how the system works for usual currencies.

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Seller asks the bank if the Buyer has money in the bank

Buyer requests a purchase

Bank updates the bank account against the purchase Seller

Buyer

Bank Bank confirms that there is money in the bank

Purchase goes through

In the case of Cryptocurrencies, there is no centralised banking system. The entire system works on blockchain. A blockchain replaces the role of the bank in this case. This process is modified in the following way: Seller seeks a confirmation from the blockchain if the buyer has sufficient Cryptocurrency

1 Buyer requests a purchase

Blockchain

Seller

Buyer Purchase goes through

Blockchain confirms that the Buyer has the amount required

A block containing information on the purchase is added to the blockchain and the buyer’s balance is updated

For normal currencies, the bank, as a financial institution, knows all about every transaction and the account details of every person involved in the transaction. How does it work in case of cryptocurrencies? Let us look at these points to find out how the blockchain system works for Cryptocurrency.

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Confirming the cryptocurrency with the buyer: Since blockchain is a decentralised and transparent system, every piece of information is available for confirmation. Hence, the amount of cryptocurrency that the buyer holds can be double-checked. Making the purchase safely: A new block is added to the blockchain that contains information about this transaction. The entire blockchain now knows how much currency was spent on this purchase. Account updation after purchase: Once the buyer has bought an item, this information is added to the blockchain as a new block. This amount is deducted from the buyer’s initial sum of cryptocurrency. This new amount is now available for buying things in the future. Trusting the information: Since Cryptocurrency is purely digital, it is always possible for the buyer to say that they have more money than what they actually have. How can we make sure, then, that the information is true? We do not have a bank in the case of Cryptocurrencies, but the information regarding the amount is held within the blockchain. This information has been verified by multiple users and records can be doublechecked at any time and from any place.

Do It Yourself 4B 1

Match the Following: Term

Cryptocurrency

Physical coins and banknotes used for buying

Traditional Currency

A famous example of a cryptocurrency

Bitcoin

Description

Digital currency that works on blockchain

Compare traditional currencies (like INR, USD) with cryptocurrencies (like Bitcoin). List at least two similarities and two differences between them.

Points to Remember 1

Blockchain is a digital technology for storing and securing information.

Blockchain is decentralised, meaning no single person or authority controls it.

A blockchain is a digital network composed of blocks.

Each block is a specific unit of data within a blockchain that holds information.

Blocks hold verified information and cannot be changed or deleted.

Information within a blockchain is transparent but safeguarded against unauthorised changes.

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Interoperability is a limitation of blockchain, as different blockchains might struggle to communicate due to design differences.

Transactions are recorded as blocks on the blockchain.

Cryptocurrency is a type of digital or virtual currency that serves as a medium of exchange.

10 Cryptocurrency exists only in digital form and lacks physical existence. 11 Bitcoin is an example of a cryptocurrency.

Chapter Checkup A. Fill in the Blanks. Hints

block

individuals

blockchain

bank

privacy

The specific unit of data that is part of a blockchain and holds verified information is called a

The information stored in a

Blockchain ensures

Decentralised means that the control or decision-making is spread out among many different

Cryptocurrency is based on blockchain technology. It is not controlled by any

is divided into blocks. so that the individual and personal details of participants are secured. .

or any government.

B. Tick () the Correct Options. 1

Which of the following statements about blockchain is incorrect?

a Anyone can easily change information in a blockchain. b Blockchain uses blocks to store information. c The information stored in a blockchain is secure. d Blockchain utilises decentralisation and security features to store information. 2

Which feature of blockchain allows everyone in the network to see the entire history of the data?

a Security

b Transparency

c Privacy

d Immutability

In a blockchain, each new block needs to be verified by:

a the buyer

b every individual on the blockchain

c the seller

d a portion of blocks

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What challenge can arise due to the decentralised nature of blockchains and their potential differences in design?

a Enhanced communication between blockchains. b Simplified data sharing among different blockchains. c Improved interoperability between various blockchain networks. d Difficulty in communication between different blockchains.

C. Who Am I? 1

I am a digital technology that connects pieces of information in a secure way.

I am a type of currency that exists only in digital form and works on blockchain technology.

While withdrawing regular currency notes, I maintain a record of the transaction.

I am a national currency used to buy things in India.

I am a unit of data in a blockchain that holds specific verified information.

D. Write T for True and F for False. 1

Decentralised means there is one central authority controlling everything.

Blockchain can be used to create transparent voting systems where every vote is recorded and cannot be altered.

If your school uses a blockchain-based digital identity system for students, you cannot view other students’ personal information.

Cryptocurrencies have a banking system that records transactions, similar to traditional currencies.

In a blockchain network, any user can easily access, change or delete the information stored in a block.

E. Answer the Following. 1

What are blockchains? Think of an example that can work on a blockchain.

Describe the features of blockchain.

How does blockchain ensure the security and integrity of information?

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How does the transparency of a blockchain system help build trust among users?

Briefly state the challenges of blockchains.

F. Apply Your Learning. 1

Imagine a school club where everyone gets to make decisions. Is this like a decentralised system? What could be some strengths and weaknesses of such a system?

Suppose your school library considers using blockchain technology for the process of issuing and returning library books. As a student, what benefits do you think this will have? Also, list two concerns that you might have about this idea.

Imagine if anyone could change their Cryptocurrency balance to show that they have more money than they actually do. What could go wrong in such a case? How does the blockchain prevent this from happening?

We saw in the chapter how the purchase of artwork could potentially work on a blockchain. How is this different from the usual digital purchases?

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Chapter 4 • Blockchain

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Chapter 5 • Computational Thinking

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Chapter 5 • Computational Thinking

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Problem-Solving A problem is a challenge or a task that needs to be solved.

Puzzles are problems that challenge our thinking skills. There are many types of puzzles that we solve, such as jigsaw puzzles, Sudoku, riddles, maths puzzles, and more. Let us solve the maths puzzle. You need to enter the correct numbers in the blank spaces so that all the calculations are correct.

× ×

Look at the first row. It is already done for you: 14 ÷ 2 = 7. Now, solve the remaining puzzle in the same way. You must have noticed that in order to solve a problem correctly, we break it down into steps: Step 1: Understand the problem clearly. For example, in the puzzle, we have to understand that we need to find the missing number in each calculation. Step 2: Break the problem down into smaller parts. For example, we can write the entire puzzle as separate calculations. 14

Step 3: Solve each calculation one at a time. This process of breaking down any problem to efficiently solve it is called Computational Thinking. We use computational thinking in various fields such as engineering, medicine, social sciences, agriculture, and many other fields.

Think and Tell

Share a situation where you have used Computational Thinking in real life.

Concepts of Computational Thinking Computational thinking can help us develop the skills we need to solve problems. Let’s learn more about it.

Decomposition Decomposition means breaking down a complex problem into smaller subproblems. This helps in understanding the problem’s structure, identifying its key components, and then solving them one at a time.

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Suppose you want to go on a trip to Nainital. Before the trip, you need to ensure that everything is arranged. Here, the problem statement is to check if all the arrangements for a trip to Nainital are done. Now, let us break down this problem into smaller subproblems: 1.

How many travellers are there?

When is the departure date?

When is the arrival date?

How long will the trip last?

What are the places to visit?

PROBLEM

SUB PROBLEM 2

SUB PROBLEM 1

Pattern Recognition Pattern recognition means finding similarities or patterns within a problem. This can lead to more efficient solutions. Identify the pattern and fill in the empty boxes with colour.

Now, to identify the places to visit in Nainital, we need to identify the pattern of people frequently visiting places.

The technique we use to identify the most visited places is pattern recognition. Pattern recognition is also applied when we observe our current problems and check if a previously identified solution can solve them.

Let us look at another example of pattern recognition. Observe the given table:

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Do you recognise a pattern? The values of Y are double the values of X. That is the pattern we can notice here.

Think and Tell

Give another example where pattern recognition can be helpful.

Abstraction

Abstraction means focusing on the most important parts and ignoring the details that don’t matter. Imagine you want to go a hike during your trip. You can bring a map of the hiking route with you. Maps are a great example of abstraction. They don’t need to include everything in Nainital; they can just focus on the hiking route you will take. This way, they can leave out all the unnecessary details on the map that you don’t need to know to go on this hike.

Algorithmic Design In computer science, the set of steps that solves a specific problem is called an algorithm. Therefore, algorithmic design means creating step-by-step instructions to solve the subproblems. This involves determining the specific sequence of actions needed to arrive at a solution. While tracking, when we reach the top, we need to set up a tent to spend the night there. Let us look at the steps to set up the tent: 1.

Find a clean, flat spot.

Lay out the tent and its parts.

3. Connect the sticks and put them through the tent. 4. Attach the cover and secure it with pegs.

Explore More!

5. Double-check everything to make sure it’s set up right.

Know more fun-filled things about computational thinking here!

This set of steps makes the task of building the tent much easier.

Do It Yourself 5A 1

Read the scenario and answer the question. Projects to Complete

Due Date

Maths

19 August

Social Studies

17 August

Science

19 August

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You have three class projects due this week. You look at your diary to see when they are due. You see that the maths and the science projects are due in three days, but the social studies project is due tomorrow. You decide to focus on the social studies project first because it is due sooner. Which concept of computational thinking is applied here?

Rina was riding her bicycle to school when her bicycle tyre got punctured. She fell off the cycle, but she didn’t get hurt. However, her pen fell out of her bag. Match the following: Concept Name Decomposition

Pattern Recognition

Example She had a flat tyre before, and she knows a shop close by where she can get it repaired.

1. Punctured tyre. 2. Lost pen.

Abstraction

I should take the bicycle to the nearby mechanic.

Out of the two problems, she decided to focus on getting the tyre fixed because she needed to reach school on time.

To get the tyre fixed: 1. Go to the tyre shop. 2. Ask the mechanic to fix the tyre. 3. P ay the mechanic and get your bicycle back.

Algorithmic Design

She identified the subproblems: 1. Punctured tyre. 2. Lost Pen.

Label the images to correct the concept of computational thinking.

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Write the steps for the image. Sugar Milk

Baking powder

1. 2. 3. 4. 5. 6. 7. 8. 9.

Flowchart A flowchart is a pictorial representation of an algorithm.

A flowchart uses symbols and shapes to represent various elements such as inputs, outputs, and decisions. These symbols are connected by arrows to show the logical flow of the process.

Explore More! A flowchart helps us in various real-life situations.

Here are some of the most commonly used flowchart symbols: Symbol

Name Terminator

To show the start or stop of the flowchart

Input/Output

To show input or output.

Process

To show a process step. For example, sum = a+b

Decision

To show a decision statement where the program can take one of the two paths based on the yes/no answer.

Flow line

To show the direction in which the process flows.

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Purpose

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We wrote an algorithm to bake a cake. Observe the flowchart for it. Start

Terminator

Gather the ingredients—flour, sugar, eggs, milk, and baking powder.

Input

Sieve the flour to ensure a smooth texture.

Process

Add and mix sugar, baking powder and milk to form a batter.

Process

Pour the batter into a cake pan.

Process

Put the pan in the oven. Cook it until it is golden brown.

Process

Take the cake out of the oven and let it cool for a bit.

Process

Spread a layer of frosting on top of the cake.

Process

The cake is ready to be eaten.

Output

Stop

Did You Know? Frank Gilbreth, an American engineer, and his wife Lillian were the first to introduce flowcharts.

Terminator

Explore More!

There are many tools available for creating flowcharts. One such tool is Lucidchart.

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Do It Yourself 5B 1

Find the mistake in the following flowchart. Draw the correct flowchart in the space provided. a.

Start

Correct Flowchart

Read three numbers a, b and c

average = (a + b + c) / 3

print average

Stop

Start

Correct Flowchart

Read F

C = 5 / 9 * (F – 32)

print C

Stop

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When driving a vehicle or walking on the street, it’s crucial to obey traffic light rules. With numerous vehicles on the road, not following these rules can cause accidents. Create an algorithm and flowchart based on this scenario. Algorithm

Flowchart

Complete this flowchart to check if a number is even or not. Write instructions in the empty boxes and draw appropriate shapes around the steps which are not inside a shape.

Read the number Is the number divisible by 2? yes

Print "odd number"

Stop

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Points to Remember 1

Problem-solving involves finding solutions to various challenges.

Computational thinking is a way of thinking to solve a problem. It uses the concepts of computer science.

Computational thinking can be applied not only to computer science but also to fields like engineering, medicine, social sciences, and more.

The four components of computational thinking are:

a Decomposition: breaking complex problems into smaller subproblems. b Pattern Recognition: recognising patterns within a problem and using previously identified solutions. c Abstraction: focusing on essential details while ignoring irrelevant information. d Algorithmic Design: creating step-by-step instructions to solve subproblems. 5

Algorithmic design means creating step-by-step instructions to solve the subproblems.

A flowchart is a pictorial representation of an algorithm, using standardised symbols.

Symbols in flowcharts represent elements like start/stop, process steps, input/output, and decisions, connected by flow lines.

Chapter Checkup A. Fill in the Blanks. Hints

algorithm

subproblems

pictorial

essential

Computational thinking is a problem-solving approach that utilises concepts from

Decomposition involves breaking down a complex problem into smaller

Abstraction focuses on the

A flowchart is a

computer science . .

details of a problem while ignoring irrelevant information.

is a set of instructions that solves a specific problem. representation of an algorithm.

B. Tick () the Correct Option. 1

Symbols in a flowchart are connected by

a flowlines

b input

c decisions

d process steps

Pattern recognition helps to identify

within a problem.

a solutions

b complex algorithms

c similarities or patterns

d inefficiencies

Algorithmic design involves creating step-by-step instructions to solve

a complicated maths problems

b unrelated puzzles

c subproblems

d computer hardware issues

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Which of the following is a real-life example of an algorithmic design?

a Following a recipe to bake a cake.

b Following a set of instructions to build a model.

c Following a set of steps to solve a maths problem.

d All of these.

What is the purpose of a flowchart in problem-solving?

a To introduce complex concepts.

b To represent irrelevant information.

c To provide a clear visual representation of an algorithm.

d To confuse the problem-solving process.

C. Who Am I? Statement

Symbol

Is a > 5? sum = 4 + 6 + 10 Stop Print “Hi” Start

D. Write T for True and F for False. 1

Problem-solving involves finding solutions to challenges, and it's applicable only in professional life.

Decomposition is the process of breaking down a complex problem into smaller subproblems.

An algorithmic design includes creating step-by-step instructions to solve subproblems.

Each step of an algorithm should be well-defined and unambiguous.

Pattern recognition is another key concept in computational thinking. Pattern recognition means finding similarities or patterns within a problem.

E. Answer the Following. 1

What is algorithmic design, and how does it provide a systematic approach to solving problems?

What is decomposition?

What are the different symbols used in flowcharts?

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What is abstraction?

What are the four components of computational thinking?

F. Apply Your Learning. 1

Ronit wants to find the factorial of a number. Write an algorithm to find the factorial of a number.

Prerna had saved ₹2,000 in the bank for 5 years at the rate of 15% interest per year. Draw a flowchart to calculate the simple interest.

Riya wants to bake a birthday cake. She decides she will bake the cake first because she can make the frosting later while the cake cools down. Which concept of computational thinking has she applied?

Observe the following statement: “Check if 6 is divisible by 2 or not.” Which flowchart symbol should we use for the statement?

What is wrong with the following flowchart? Read a and b

Result = a * b

Print Result

Stop

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Chapter 6 • Formulas and Functions

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Chapter 6 • Formulas and Functions

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Understanding Spreadsheets Let us say your parents allowed you to have lunch with your friends in the school canteen. Can you find out how much money you and your friends spent in the canteen altogether? Yes, you can with the help of a spreadsheet! A spreadsheet is a tool that helps you organise data in rows and columns and do calculations. Spreadsheets also allow you to analyse and visualise data. There are many spreadsheet software options available, such as Microsoft Excel and Google Sheets. While Excel is a licenced software, Google Sheets is free. Google Sheets lets you create spreadsheets online and collaborate with others.

Creating a Spreadsheet Let us create a spreadsheet to track how much money you have spent eating in the canteen. To do this, follow the given steps: 1. Open the Google Chrome browser and visit the link: https://docs.google.com/spreadsheets/ 2. The home page appears, as shown below. Click on the plus ‘+’ sign to open a blank spreadsheet.

3. In your new spreadsheet, go to the Rename textbox given at the top left corner of the sheet and rename the file as, “Canteen Expenses”.

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Elements of a Spreadsheet A spreadsheet consists of a grid-like structure. The various components of a spreadsheet are discussed as follows: Column/Field Row: The horizontal set of boxes is called a row or record. Column: The vertical set of boxes is called a column or field.

Row/Record

Cell: The intersection of a row and a column is called a cell.

Cell

Cell Naming A cell is a rectangular block in the sheet that can hold data. Column A

Data can be numbers, strings, or symbols. To refer to a cell, we use cell names. A cell name is a combination of letters and numbers. Letters represent the column, and numbers represent the row.

Row 1

For example, look at this image. The first cell will be called A1, where A stands for the column and 1 stands for the row. Now, let us start entering the data in the sheet. Follow these steps:

Cell name A1

1. Select a cell where you want to add data using the mouse or the arrow keys. 2. Type in numbers, text, or any other information you want, to add data. 3. Press the Tab key to move to the next cell in a row. 4. Press the Enter key to move to the next cell in a column. Now, type the data as shown in this image.

Applying Formulas Now that you have added the details of your expenses, let us apply a formula to find the total expense. To do so: 1. Select the cell where you want the total to appear, for example, cell B13. 2. Type the equals sign ‘=’. 84

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3. Now, click on the cell B3, type a plus ‘+’ symbol, and click on cell B4. 4. Repeat this process up to cell B12 and then press the Enter key. The sum of cells B3 to B12 will appear in cell B13. Similarly, to find the average price, you need to divide the total amount of expenses by 10, as there are ten cells that have the “Price” data. To do so: 1. Select the cell where you want the average to appear. For example, B14. 2. Type the equals sign ‘=’. 3. Now, click on the cell B13, type ‘/’ symbol after 190, for division; and then type “10”. 4. Press the Enter key. The average of values will appear in the cell B14.

Explore More!

You can also insert images in the cell.

14 15

Do It Yourself 6A 1

Match the highlighted cells with their correct cell names. Cell

Cell Name E1

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Write the formula to calculate the total of cells B1, C1, and D1 in cell E1.

Functions You have learnt in the previous section how to calculate the sum and the average price of items using formulas. However, you could have simplified your formulas by using functions. Now, let us learn a quicker way to find the sum and average using functions. Functions allow you to calculate more efficiently using cell ranges instead of typing out the name of each cell. A cell range is a group of cells selected together. We can apply functions to cell ranges. Functions are like built-in formulae in Google Sheets. They perform calculations, handle data, and analyse information. When we want to use a function on a range of cells, we type the range instead of typing the name of each cell. To type a cell range, first we type the name of the first cell, then a colon (:), and then the name of the last cell. For example, A1:A4. To use a function, first type the ‘=’ sign, then the function name, followed by cell names or cell ranges inside the brackets. For example, =SUM(A1:A4) Let us try functions in place of formula to find the total expense and average of items.

FUNCTION NAME CELL RANGE

Using the SUM() Function The SUM( ) function is used to add the values given in a specific cell range. To use the SUM( ) function, follow the given steps: 1. Click on the cell where you want the sum to appear, for example, cell B13. 2. Type an equal to symbol ‘=’ and then the function name SUM. 3. Type the opening parentheses ‘(‘ after the function name. 4. Inside the brackets, add the cell range for which you want to calculate the total. For example, B3:B12. 5. Press Enter to complete. You can see the result in the cell B13. 86

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Using the AVERAGE() Function The AVERAGE() function is used to find the average of a set of numbers. To use the AVERAGE() function, follow the given steps: 1. Click on the cell where you want the average to appear, for example, cell B14. 2. Type symbol ‘=’ and then the function name “AVERAGE”. 3. Type the opening parentheses ‘(‘ after the function name. 4. Inside the brackets, add the cell range for which the average is to be calculated, that is, B3:B12.

5. Press Enter to complete. You can see the result in cell B14.

Common Functions Used in Google Spreadsheets Let us look at some more functions that are used in Google Sheets. Refer to the cell addresses used in the chapter for the examples given. Function Name PRODUCT

Purpose Multiplies the values in the specified range of cells

=PRODUCT(B3:B5)

MOD

Returns remainder when the dividend is divided by the divisor.

=MOD(Dividend, Divisor) =MOD(B3,B12) Output: 5

SQRT

Returns the square root of a number

=SQRT(B3)

INT

Rounds the number to an integer value

=INT(number) =INT(3.2)

POWER ABS COUNT

Output: 7500

Output: 5 Output: 3

Returns the result of raising a number to a specified power =POWER(cell, power) =POWER(B4, 2) Output: 100 Returns the absolute or non-negative value of a given number

=ABS(number) =ABS(-23) Output: 23

Returns the count of the number of values in a range of cells =COUNT(B3:B12)

Output: 10

MIN

Returns the lowest value in a range of cells

=MIN(B3:B12)

Output: 10

MAX

Returns the highest value in a range of cells

=MAX(B3:B12)

Output: 33

Verifies if the provided condition is met. It returns the value 1 when the condition is true or the value 2 when the condition is false.

= IF(condition, value_if_true, value_if_ false) = IF(B3>18, “Affordable item”, “Costly item”) Output: Affordable item

Combines multiple text strings into one

=CONCATENATE(A4, A10) Output: ChipsPatty

LEN

Returns the length of the text string

=LEN(A2)

UPPER

Converts the text into uppercase

=UPPER(A12)

Output: SANDWICH

LOWER

Converts the text into lowercase

=LOWER(A6)

Output: orange juice

TODAY

Returns the current date

=TODAY()

NOW

Returns the current date and time

=NOW()

CONCATENATE

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Example

Output: 4

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Think and Tell

You are tracking the number of hours you study, for different subjects, in a Google Sheet. Which function would you use to find the subject that you have studied the longest? Hint: Refer to the table given above.

Discuss!

How are formulas and functions different?

Do It Yourself 6B 1

Label the parts of the given function.

=MIN(B1:B6)

A group of friends went on a trip. Their individual expenses are given in the table below. Calculate the total and average expense of the trip in the cells B10 and B11, respectively.

Explore More!

Create your own Random Number Generator game!

Sorting Sorting means to arrange data in a particular sequence based on specific criteria. It allows us to reorganise data in rows or columns, making it simpler to locate, analyse, and understand. Let us again consider the example of the canteen expense sheet. Suppose you want to find out which item is the most expensive. Then, you can sort the data of the sheet in descending order. To do so, follow the steps: 1. Choose the range of cells that contains the data you want to sort. 2. Go to the Data menu. 3. Select Sort range > Advanced range sorting options from the menu. 88

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4. A dialog box appears. In the Sort by drop-down, select Column B and then check Z to A checkbox to arrange data in column B in the descending order.

Grouping of Data Suppose you are interested in finding out how many items have the same price in the canteen expense sheet. This way, you can display each snack item just once, without repeating it multiple times. This is done with the help of grouping of data. In Google Spreadsheets, grouping means putting similar things together. Grouping keeps things tidy and helps you find what you need faster. Follow the steps to group data of the canteen expense sheet: 1. Sort the data in ascending order by column B in the canteen expense sheet.

2. Select the rows that you want to group. Then, go to the View menu. 3. Select the Group option > Group rows 4-5.

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4. Use the plus ‘+’ button to show the group and the minus ‘−’ button to hide the group.

Filtering Data Suppose you want to see only those items that cost more than ₹20. To resolve this, another powerful feature is used, called Filters. Filters are a useful feature used in Google sheets that enables you to display data according to specific criteria. Filters can help narrow down the options to what we want and hide the rest. Filtering allows us to focus on specific parts of our data that meet certain conditions. By using filters in spreadsheets, you can easily find specific data, answer specific questions, and understand information in a better way. Let us try to filter data to find items that cost more than ₹20 in the Canteen Expense sheet. 1. Select the range to which you want to apply the filter. 2. Go to the Data menu and choose Create a filter option.

3. Click on the Filter symbol and select Filter by condition and choose your rule. 4. After selecting the required rule, click OK.

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5. The spreadsheet hides unmatched rows, showing only the data that fits the chosen criteria.

Discuss!

How is filtering different from grouping?

Do It Yourself 6C 1

You have a list of animals in a spreadsheet, and you want to see only the ones that are mammals. What should you use?

a Sorting b Filtering c Formatting d Deleting 2

Write T for True and F for False.

List of Animals

Animals

Class

Lion

Mammals

Shark

Fish

Crocodile Tortoise

Reptiles Reptiles

Giraffe

Mammals

Kangaroo

Mammals

Elephant

Mammals

a You have created a list of cars and their speeds in a Google Sheet. You can use the sorting

feature to put them in order from the highest to the lowest speed to view the fastest car at the top.

b Grouping data is only useful when working with numbers, and it doesn’t apply to other types of information.

Charts Charts help us look at data in the form of pictures. This helps us to understand the data in a better way. Charts are common in everyday life, such as weather forecasts on TV. These charts use images and colours to display daily temperatures or chances of rain. Just like looking at the weather without too many numbers, charts help us see information in pictures, making it easier for our eyes and brains to quickly understand. Chapter 6 • Formulas and Functions

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In Google Sheets, there are various types of charts available to visually represent data. Let us explore some common types of charts: Column Chart: It uses vertical bars for comparing data or showing quantities. Each bar represents a category, and its height shows the value or amount. Bar Chart: It is similar to a column chart but with horizontal bars.

Aama Shruti Daisy Faisal Garima 0

Pie Chart: It displays parts of a whole as slices of a pizza. Each slice represents a category, and its size shows the proportion or percentage.

Line Chart: A line chart uses lines to show how something changes over time by connecting dots. This helps us spot trends, such as temperature changes throughout a year or the progression of a plant’s growth.

Creating a Chart 1. Choose the cells that contain the data you want to present in the chart.

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2. Go to the Insert tab and select the Chart option.

3. A chart will appear along with a Chart editor menu on the right-hand side of the page. 4. Select the appropriate type of chart from the Chart editor menu. In this example, we are creating a stacked column chart.

5. Once you have selected a chart type, you can customise it from the customise section in the Chart editor menu. As you can see in the image, the background is changed to grey, and the 3D version of the chart is enabled.

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Sheet Tabs So far, you have been working on the Canteen Expense sheet. If you want to track your subject marks throughout the year, you do not need to create a new spreadsheet. Instead, you can keep adding new sheets in the same spreadsheet.

Explore More!

There are plenty of different types of charts in Google Spreadsheets.

To add a new sheet tab in Google Sheets, follow the given steps: 1. Click on the plus ‘+’ symbol at the bottom left corner of the Google sheet. 2. A new sheet tab will appear, ready for you to work on.

Colouring Sheet Tabs Colouring sheet tabs in a Google Spreadsheet means giving different colours to the names of the sheets. Let us colour-code the sheet tabs to organise the spreadsheet, making it easier to find the information you need. The steps for colouring sheet tabs are: 1. Right-click on the tab you want to colour. 2. Click on the Change color option. 3. A palette of colours will be displayed. Select the colour you like by clicking on it. The sheet tab will be coloured.

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Do It Yourself 6D Tick () the correct answer.

Why do we use charts in Google Sheets?

a To make the data look fancy b To make the numbers bigger c To help understand and analyse data more easily d To hide the data from others 2

Which type of chart looks like a pizza divided into slices?

a Bar chart

b Line graph

c Pie chart

d Scatter plot

Points to Remember 1

A spreadsheet is a tool that helps you organise data and do calculations.

A cell is a rectangular block in the sheet that can hold data.

A cell name is a combination of letters and numbers.

Functions are pre-built formulas that you can use to perform various calculations or operations on your data.

A cell range is a group of cells selected together.

ome functions are: SUM (adding numbers), AVERAGE (finding the mean value), MAX (finding the highest S value), MIN (finding the lowest value), and COUNT (counting the number of cells with numbers).

Sorting refers to arranging data in a particular sequence based on specific criteria.

In Google Spreadsheets, grouping means putting similar things together.

he purpose of filters in Google Sheets is to help you view and analyse specific subsets of data within a T larger dataset.

10 Charts are a method of presenting data as visual representations that make understanding information easier.

11 Column Chart uses vertical bars for comparing data or showing quantities. 12 Bar Chart is similar to a column chart, but with horizontal bars. 13 Pie Chart displays parts of a whole as slices of a pizza. 14 A line graph uses lines to show how something changes over time by connecting dots. 15 Colouring sheet tabs in a Google Spreadsheet means giving different colours to the names of the sheets.

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Chapter Checkup A. Fill in the Blanks. Hints

A1:A5

letters, numbers

length

average

visual

A bar chart is like a graph made up of colourful rectangular bars, where each bar represents a category, and its shows the value or amount.

The

Charts are

A cell name is a combination of

The SUM function helps us add numbers together. To find the sum of a group of numbers, we can use the formula “=SUM(A1:A5)”. Here, represents the range of cells.

function helps us to find the mean of multiple numbers in spreadsheets. representation of data. and

B. Tick () the Correct Option. 1

Consider a list of toys and their prices. What function will you use to view the price of the most expensive toy?

a AVERAGE

b SUM

c MAX

d COUNT

Grouping in spreadsheets refers to:

a Colouring sheet tabs

b Arranging data in a specific order

c Combining related rows or columns together

d Creating formulae to perform calculations

What do charts do in spreadsheets?

a Perform calculations

b Show data visually and help understand it

c Sort data alphabetically

d Change the font style of the spreadsheet

What do functions do in spreadsheets?

a They organise your files

b They make spreadsheets look colourful

c They do specific tasks with data

d They create fun animations

Formulae in spreadsheets are used for:

a Changing the font style of cells

b Performing calculations and handling data

c Applying filters to data

d Grouping rows and columns

C. Who Am I? 1

I am a special command in spreadsheets that automatically handles complex calculations or data tasks.

I am a function in spreadsheets that gives you the number of cells in a range containing data.

I am a type of chart that uses colourful and rectangular vertical bars to compare quantities or values.

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I am a process in spreadsheets that involves arranging data in a specific order based on certain criteria.

I am a symbol used to add sheet tabs in Google Sheets.

D. Write T for True or F for False. 1

Pie charts are suitable for comparing quantities or values, while line graphs are used to show changes over time.

Filtering data in spreadsheets permanently removes hidden rows or columns from the dataset.

Sorting in spreadsheets refers to arranging data in a specific order based on certain criteria, making it easier to locate and analyse.

The COUNT function in spreadsheets counts both numerical values and empty cells within a range.

E. Answer the Following. 1

What is the basic element of a spreadsheet called and what does it hold?

What formula would you use if you want to multiply all the values in cells B1 to B7?

What are the different criteria for arranging data?

Why are functions used in spreadsheets? Name any five basic functions.

What type of chart would be appropriate to display the names of TV shows and the number of students who like each show?

F. Apply Your Learning. 1

Ishita has to organise a list of words in dictionary order. What methods should she use to convert List 1 into List 2?

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Arjun gets ₹400 as pocket money every month. He spends some money and saves the rest. He uses spreadsheets to list his savings for each month. Using the spreadsheet given below, answer the following questions: a. Which formula should he apply to get his total savings per month? b. What is the cell name he might get the total value at?

Somya wrote the text in lowercase instead of uppercase. What function should she use to convert the text to uppercase?

my name is somya arora. 4

MY NAME IS SOMYA ARORA.

Raj has created several tricky questions for his friends to guess the function he has used in the result column. Write down the formulas in the blank boxes.

Column 1

Column 2

Result

Formula

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Chapter 7 • Database

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Chapter 7 • Database

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Introduction to Database We are in an age where we are surrounded by a huge amount of data. Data helps us maintain and improve systems. Think about your school. Your school needs to maintain data about all the students, like their names, ages, grades, library card numbers, parent’s names and many other details so that the school can run without any problems. Similarly, data helps shopkeepers to keep track of their sales. Large businesses benefit from data by being able to understand their customers and create products that will be helpful to them. Additionally, it aids scientists in their many scientific endeavours. However, storing and maintaining this data on the computer becomes a challenge if we do not have a structured system. It leads to various problems like having the same information in different places, information not getting updated everywhere, and security and privacy issues. To resolve these problems, we use databases. A database is a collection of information or data, stored electronically in a computer system. Most databases store data in the form of tables. A database can contain multiple tables to store related data. For example, your school’s database might contain separate tables containing students’ data, teachers’ data, library data, and so on.

The column headers in the table are known as attributes and the rows are known as records. We use DBMS (Database Management System) to organise and manage the databases. It acts as an interface between the database and user applications. We will learn more about DBMS later in this chapter.

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Database

Did You Know? DBMS

The first DBMS was developed in the early 1960s by Charles Bachman.

Importance of Database In this digital age, computers are used everywhere to store large amounts of data to keep track of personal and professional needs whether it is a local grocery shop or the stock market. Today, we all rely on some form of database to store information. Let us learn more about the importance of database: Organised Information: Databases help to keep information organised and make it easier to find. Most databases store related data using multiple tables. This information is recorded in rows and columns, making it easy to access. Quick Access: Without a database, you would need to manually search through various files and documents to find data. Databases make it simple to add, delete, or modify data because they store data in rows and columns, allowing quick access to specific information. Centralisation: Centralising information also structures data and prevents duplication. It saves space and allows you to work better and faster, ultimately increasing your overall productivity. Large Volume of Data: Databases can store and organise a huge amount of data easily. That makes it easy to quickly find the specific information as needed. Data Security: Your data is secure when it is kept in the database. Only authorised persons can access the information which prevents unauthorised access to data. Ensures Data Integrity: Data integrity is a process that makes sure the data is correct, whole, and the same as long as it exists in the database. The database ensures data integrity by providing accurate information, even if multiple users are working in the system at the same time. This means you will always get the right information, even when there are multiple users. For example, Book Id, Book Name, Genre, Price and Publisher would be the same throughout, and anyone can access it. Data integrity helps to set rules on how this data can be accessed, used, and modified.

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Reduction of Data Redundancy: Data redundancy occurs when we have multiple copies of the same data. Databases help us reduce data redundancy by making sure you do not have copies of the same data spread all over the place. This is important because it can get tricky to update data everywhere it is stored. As we have understood the importance of databases, let us learn more about Database Management System.

Explore More!

Big Data is a huge collection of information. Companies use it to recommend movies and songs you might enjoy.

Database Management System (DBMS) A DBMS (Database Management System) is software that helps us to store, retrieve and manage data in a database. To retrieve data means to obtain the data from the database. It provides an interface between an end-user and a database, which allows users to create, read, update and delete data in the database. It also provides protection and security to the database. In case of multiple users, it can restrict access to different databases for unauthorised users. Imagine you have a big collection of books and you need someone to keep them neat and tidy for you. That’s what a DBMS does for databases. It helps organise the data, makes it easy to search for specific things, and ensures that everything is safe and secure. So, whenever we want to find something in our database, the DBMS helps us quickly locate the exact information we need.

Discuss!

What is the difference between a database and a DBMS?

Components of DBMS Database Management System consists of six main components. These are: 1. Hardware 2. Software

Software Hardware Components

3. Data 4. Procedures 5. Database Access Language 6. People Chapter 7 • Database

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Data

Procedures

of DBMS

People

Database access language

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1. Hardware: The hardware of computers consists of physical components such as a keyboard, mouse, monitor, and processor. Hardware is used to capture the data and present the output to the user. When we try to run any database software like MySQL, we can type any command with the help of our keyboard. Storage devices, such as the hard disk, RAM, and ROM, are also the part of our computer system. 2.

Software: Software is a set of programs that help hardware do its job.

It is made up of procedures and programs that can understand the language used to talk to databases. This software then turns those instructions into real commands for the database and makes things happen. Some examples of DBMS software are MySQL, Oracle, SQL Server, dBase, FileMaker, Clipper, and Microsoft Access. FoxPro is a discontinued DBMS developed by Microsoft.

Did You Know? Smarthome gadgets, like those controlling lights and music, rely on databases to deliver great experiences.

3. People: People interacting with the computers are also referred to as the “live-ware” of the computer system.

They form the most crucial part of the computer system.

These individuals control and manage databases, performing various operations within the Database Management System (DBMS). This group comprises the database administrator, software developer, and end-users. 4. Procedures: A procedure is a form of general instructions or guidelines for using a DBMS. These instructions include how to set up the database, install it, log in and out, manage it, create a backup, and generate reports from the database. 5. Data: These are the actual pieces of information, like numbers or text, that are input into a computer system.

“Data” refers to the collection of raw facts stored in a database.

Data is the fundamental building block for creating useful information. It is a crucial part of a DBMS. The database contains both the actual data and metadata, which is information about the data. For example, when you want to store data in a database, you need to identify the attributes to organise that data, such as the data’s size, name, and other related details. These specific pieces of information about the data to be stored are known as metadata.

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6. Database Access Language: Database Access Language is a language that allows users to give commands to a database to operate the data stored. You can use this language to ask the database to do many things, such as getting data, modifying it, or removing it. The most widely used Database Access Language is SQL. SQL stands for Structured Query Language.

Do It Yourself 7A 1

Match the Columns. Column A

Column B

Database

Occurrence of duplicate copies of similar data

Data Integrity

A special computer program for managing databases

Database Management System

A collection of organised data

Data Redundancy

A process that makes sure data is accurate, complete, and consistent over the data’s lifecycle

MySQL MySQL is a database management system that allows us to create our own databases. It allows us to create, update, and retrieve data using SQL. It is open-source, which means it is free to use. It is popular for its speed, reliability, and scalability.

SQL (Structured Query Language) SQL (Structured Query Language) is a language that lets us access and manipulate databases. It allows us to perform operations on the data stored in the database, such as updating, inserting, deleting, and modifying data, etc.

???

SQL

STRUCTURED

QUERY

STRUCTURED QUERY LANGUAGE

Did You Know?

Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.

storage

010111000

database

STRUCTURED STRUCTURED

? ???? ?

SQL SQL

LANGUAGE tables

QUERY QUERY

01011100010010 STRUCTURED QUERY LANGUAGE STRUCTURED QUERY LANGUAGE

109

Chapter 7 • Database storagestorage

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databasedatabase UT24CB_G7.indb 109

010111000 010111000 tables tables

SQL is not a database management system, but a query language.

LANGUAGELANGUAGE

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SQL works on structured data. As a database holds data in a structured way, it is easy to retrieve information using SQL. With SQL, we can state our query using commands and ask the database to find specific data, like “Which book has the maximum price?” or “How many books do I have in my collection?”. The database then understands our questions and gives us the right answers. SQL is simple but a powerful language to deal with databases. Before we learn more about SQL and create our database, let’s learn about keys. Keys are used to uniquely identify any row of data from the table. We know a database can have multiple tables. Keys are also used to establish and identify relationships between tables. We will learn about 4 kinds of keys in this chapter. 1. Primary Key: The primary key is the attribute or set of attributes in a table that uniquely identifies a row in that table. There should be only one primary key in a table. The value of the primary key in each row should be unique, there should be no repetition. Let’s observe the Students table. Student_ID is the primary key. Student_ID uniquely identifies each row in the table. In tables, the underlined attribute is the primary key. Student_ID

Student_Name

STU001

Riya Das

STU002

Ronita Shah

STU003

Anuj Bhatnagar

STU004

STU006

Satish Pandey

LIB007

LIB100

LIB101

Library_ID

LIB010

Roll_Number

Priya Sen

Section

Ritu Gupta

STU005

Grade

LIB112

LIB015

2. Candidate Key: There might be multiple attributes that can uniquely identify a row in a table. In our example, both Student_ID and Library_ID can uniquely identify a row in the table. But we had chosen Student_ID as the primary key. Candidate key is the attribute that uniquely identifies a row in the table, but is not considered as the primary key. In our example, Library_ID is the candidate key. 3. Composite key: A primary key can consist of more than one attribute. In the Students table, Grade, Section and Roll_Number when combined together can identify a row uniquely. Hence, it can be a primary key. When a primary key consists of more than one attribute, it is called a composite key. 4. Foreign key: We have previously learnt that a database can have multiple tables. Foreign keys help us to establish a relationship between these tables. Consider the following tables:

Students table: Student_ID

STU001

STU002

STU003

STU004

STU005

STU006

Student_Name

Riya Das

Ronita Shah

Grade

Section

Roll_Number

Library_ID

House_ID

LIB010

H001

Anuj Bhatnagar

Priya Sen

Ritu Gupta

Satish Pandey

LIB007

H001

LIB100

H003

LIB112

H001

LIB101

LIB015

H002

H003

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House table: House_ID

House_name

H002

Yellow house

H001 H003

Red house

Green house

Both the tables have the attribute named House_ID. House_ID is the primary key in the House table but it is not a primary key in Students table. House_ID is considered as a foreign key in the Students table. Let us create a database using MySQL.

Opening MySQL Follow the steps to open MySQL on your system: 1.

Open Command Prompt on your system.

To login to your mysql server, use the command:

Did You Know? SQL is not case-sensitive.

mysql -u root -p

Enter the password.

Now, let us create a database.

Creating a Database The SQL command to create a database is:

This command will create a database with the name mydatabase. Once you press the Enter key, the query will get executed and a database will be created.

Viewing Existing Database The command to check if our database is created and view the existing databases is:

It will return a list of all the databases.

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Creating a Table in the Database Once we have created a database, the next step is to use it to create tables. To do so, we first need to enter the database we just created. The command to enter a database:

We will add the Students table first. In the Students table, we have the following attributes – (Student_ID, Student_Name, Grade, Section, Roll_Number, Library_ID, House_ID) Here, Student_ID is the primary key. In a database, when we create a table we need to define the attributes and their data types. A data type defines what kind of data an attribute can hold. The commonly used SQL data types are:

Numeric

Character/String

Date and Time

INT

CHAR

FLOAT

VARCHAR

The command to create a table: In this example, we have created a table named “Students”. It has the following columns and data types: Column Name

Data Type

Student_Name

Varchar

Student_ID Grade

Section

Roll_Number Library_ID House_ID

Varchar Int

mysql> create table Students( –> Student_ID varchar(10) primary key, –> Student_Name varchar(100), –> Grade int, –> Section varchar(10), –> Roll_Number int, –> Library_ID varchar(10), –> House_ID varchar(10) –> );

Varchar Varchar

The command to see tables inside a database is: mysql> show tables; +----------------------+ | Tables_in_mydatabase | +----------------------+ | Students | +----------------------+ 1 row in set (0.00 sec) 112

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Now, let’s add records of the students in the table we have created. A row entry in a table is called a record. To insert a record in a table, use the command: mysql> insert into Students(Student_ID, Student_Name, Grade, Section, Roll_Number, Library_ID, House_ID) –> values (‘STU001’, ‘Riya Das’, 7, ‘A’, 23, ‘LIB007’, ‘H001’); This command will add a record in the table. You can repeat this command to add multiple records in your table. Once you have finished adding the records, you can view the records in the table using the command: mysql> select * from students; This will display all the records from the table.

Discuss!

What data types can be used to add a numeric value in the table?

Explore More!

There are other Database Management Systems besides MySQL like Microsoft SQL Server, MongoDB.

Do It Yourself 7B 1

To create a table, we use

To show data from a table, we use

Identify and write down the field names if you have to create a table named Library in the School database.

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command to define its structure. command.

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Write SQL commands to create the table for your idea and to add records.

Points to Remember 1

A database is a collection of information or data, stored electronically in a computer system.

Most databases store data in the form of tables. A database can contain multiple tables to store related data. A DBMS (Database Management System) is software that helps us to store, retrieve, and manage data in a database.

MySQL is a database management system that allows us to create our own database.

SQL is a language that allows us to communicate with databases. It helps us ask questions and retrieve specific information from the database.

The common data types that are used to define the type of data used in table are: INT, FLOAT, CHAR, VARCHAR, DATE, and DATETIME.

To retrieve data from a table, we use the SELECT statement in SQL.

Chapter Checkup A. Fill in the Blanks. Hints

structured query language

select

organise

Databases help

The appropriate data type for Roll_number field in a Student table will be

The

int

and store information. .

statement is used to retrieve data from a table.

databases and obtain the data we require.

is a unique language that enables us to communicate with

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B. Tick () the Correct Option. 1

What is a database?

a A digital assistant

b A collection of data

c A type of game

d All of these

In a table, data is stored in

a key-value pairs

b rows and columns

c chains

d None of these

SQL stands for:

a Structured Query Language

b System Query Language

c Special Query Logic

d Both a and b

The Database Management System (DBMS) is a

a hardware

b software

c machine

d data type

What does MySQL do?

a Helps you remember your favourite songs

b Takes care of your pets

c Organises and stores information digitally

d None of these

C. Who Am I? 1

A collection of data which is stored electronically on a computer system in the form of tables.

A special language that helps you communicate with the databases.

Software that helps us store, retrieve, and manipulate data in a database.

A collection of data, organised in terms of rows and columns.

A Database Management System (DBMS) based on Structured Query Language (SQL).

D. Write T for True and F for False. 1

Databases are like digital filing systems that help organise and store information.

Each row in a database table represents a specific item, like a person or a product.

To connect related information between different tables, databases use keys.

SQL stands for System Query Language, and it is used to create databases.

People are an important component of a database.

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E. Answer the Following. 1

What is a database, and how is it different from a regular notebook or folder?

What are the main components of a Database Management System (DBMS), and what do they do?

What is SQL, and why is it important in the world of databases?

Name the various data types used in SQL.

Why do websites and apps use databases to remember your preferences, such as your favourite items or usernames?

F. Apply Your Learning. 1

Riya wants to maintain a record of her vacations. Identify the field names and create a table for her.

Vijay has started his own movie theatre. He wants to keep a record of the movies he plays in his theatre. Write SQL commands to create a database and table for the same.

Rahul is a video game player. He wants to create a leadership board with each player’s name, score, and level achieved. Write the SQL commands to create a leadership board table and add records in it.

Suppose you have multiple school projects, and you need a way to keep track of them. Create a database with a table which includes the fields for the project name, submission date, and status (in progress, completed, etc).

Add a row to the table you have created for the previous question.

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Designing with Canva Canva is a free graphic design platform used to create graphics and presentations. The word ‘graphics’ refers to visual art or images. Using graphics and text, we can easily convey ideas and information to a reader. Canva is used for making various types of visuals that can be used in posters, on social media, presentations, flyers, infographics, and many more. Let us learn how to create projects with graphics using Canva!

Getting Started with Canva To get started with Canva, follow the steps: 1. Open a web browser. 2. Type www.canva.com in the address bar. The home page of the website opens. 3. Create a new account by clicking on the Sign up button. Or, log in to Canva by using your existing mail address by clicking on the Log in button. To log in to an existing account

To create a new account

After you log in, the first screen will look like the image given here. You can see a variety of design templates and tools that you can choose from. Let us create a card using Canva. The card will be on the culture of Kerala. Once you learn how to make a card, you can make another one on any other state of your choice.

Creating a Card To create a card: 1. Click the Create a design button in the top right-hand corner of the screen. A drop-down menu will appear. 2. Choose Card as the design type from the menu.

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3. A new window opens where you can design the card.

Setting a Background To set the background image for your card, follow the steps: 1. Scroll down the left-hand sidebar and then select the Background option. 2. Choose a suitable background from the list.

1 Now, you can add various elements to your design. Chapter 8 • Animations with Canva

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Adding Elements Elements in Canva are colourful images, stickers, icons, and shapes that you can easily add to your designs to make them interesting. Let us follow these steps to add some elements on the card: 1. Click the Elements option on the sidebar. A drawer menu appears. 2. Browse the various elements displayed in the menu. 3. You can also type a keyword in the Search elements box and press Enter. 4. The elements related to the keyword will appear. 5. Select an element to add. The selected element appears in the design area.

2 2 2

Adding Text Other than elements, you can also add text to your design. Follow the given steps to add text to your project: 1. Click the Text option on the sidebar. A drawer menu appears. 2. Select the Add a text box button. 3. A text box with default settings appears in the design area. 4. You can select the font style and font size from the text options displayed in the options bar above the design area. Now, type the desired text in the text box. 3 2 1

Font style

Font size

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In a similar manner, add more elements and text to your design.

Concept of Layers When you add new elements to Canva, they get placed on top of each other, creating layers of elements. A layer can be considered as a transparent sheet. Suppose you need to create a drawing with various elements. There are multiple transparent sheets with one element drawn on each sheet. Now, put these sheets on top of each other. You can observe a complete drawing with multiple elements.

Positioning Elements After all the elements are placed in the design area, you can position them as required. Let us explore the various ways to position an element or a layer. 1. Click on an element. 2. Click on Position in the Options bar. 3. A sidebar opens on the left-hand side, consisting of two tabs, Arrange and Layers. 3 2 1

Let us learn about the various options in the Arrange and Layers tabs. a. Arrange Tab In the Arrange tab, the general settings for arranging various elements appear. This panel is further divided into various sections.

Layers Arrangement Section The first section helps us with the arrangement of layers. Forward—moves the selected layer a layer above. To front—moves the selected layer to the top of the stack. Backward—moves the selected layer a layer below. To back—moves the selected layer to the bottom of the stack. Chapter 8 • Animations with Canva

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Align to Page Section This section helps you to align the elements on your page. For vertical alignment, use the options Top, Middle, and Bottom. For horizontal alignment, use the options Left, Center, and Right. Let us align the text “KERALA” in the middle of our design: 1. Select the text to be aligned. 2. Then, select the Middle option, to position the element vertically in the middle of the design page.

1 2

Advanced Section The Advanced section lets you move, turn, or resize elements in your design, using exact values. It is like using a ruler to place any element exactly where you want it. Width and Height Width refers to how wide an object is, and height refers to how tall an object is. In Canva, you can type the values to specify the exact object size. You can change the values of width and height by typing the required values in the Width and Height fields. Here, px stands for pixels. Rotate The Rotate option in Canva allows you to turn the element around at the required angle. You can use this feature to show elements from various angles.

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To rotate an element:

1. Select the element to be rotated. 2. Change the value of the Rotate field to the required angle.

Alternatively, you can also rotate elements with the help of the Rotate icon.

Hold the Rotate icon and move it to change the angle of the element.

b. Layers Tab You can use the Layers tab to view the list of the layers in your project. By dragging the layers using a mouse, you can arrange the layers from this tab as well.

Using the All Tab Go to the Layers tab and select the All tab under it.

Top Layer

Different layers in the design

Bottom Layer

Using the Overlapping Tab If there are multiple layers in a project, it becomes difficult to select the exact layer on which you want to work. In such a case, the Overlapping tab is helpful. 1. Go to the Layers tab and select the Overlapping tab under it. 2. This tab shows only the layers that overlap with a selected layer. Select the layer you are looking for and make the required changes. Chapter 8 • Animations with Canva

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Think and Tell

Imagine you are creating graphics in Microsoft Paint. You have added a few shapes and text overlapping each other. Later, you realise that the text is hiding behind the shapes. Is it possible to correct it without re-creating it in Paint? If you create the same project in Canva, how would it be helpful?

Duplicating a Layer Duplicating a layer means creating a copy of it. This can save a lot of time when you want to use the same element multiple times in a project. What if you want to add two trees? You will simply duplicate the layers. To duplicate a layer: 1. In the Layers tab, right-click the layer that you want to duplicate. A drop-down menu appears. 2. Select the Duplicate option. 3. The selected layer is duplicated.

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Deleting a Layer Deleting layers that are not needed helps maintain an organised design. To delete an element from your design, delete its corresponding layer. To delete a layer: 1. In the Layers tab, right-click the layer you want to delete. 2. Select the Delete option. 3. The selected layer is deleted.

Did You Know? As of 2023, 80 crore designs were created using Canva since its launch.

Do It Yourself 8A 1

Guess the alignment of the text “Happy Birthday” in the given designs.

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Alignment:

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Write T for True and F for False.

a The Middle and Center alignment options serve the same purpose. b The To Front option is different from the Forward option. c The To Back option places an element immediately behind the other element. d You can change the order in which the elements are layered. 3

Tick () the correct option. The Align to Page feature helps you to:

a Make elements invisible.

b Create complex designs.

c Align the elements on page.

d Change the colour of the element.

Animations Have you ever seen a flipbook? It is a small book with a series of images at various positions on separate pages. When you quickly flip through such a book, it creates the illusion of movement of the objects drawn on the pages. The cartoon movies that you watch are created in a similar fashion. Many images are drawn and flipped through at a fast pace so that the characters seem to be moving. This is what we call animation.

Did You Know? “Snow White and the Seven Dwarfs”, released in 1937, is Disney’s first full-length animated movie!

Creating Animations After creating a design in Canva, you can make it look interactive by adding animations. Canva has many useful tools using which you can create interesting animations. Let us learn how to use them.

Adding Page Animation Page animations decide how your page will enter the screen. To add page animation: 1. Select the page. (Make sure you select only the background, not the other elements.) 130

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2. Click the Animate option on the top bar. A sidebar with the tab Page Animations opens showing a list of animations. 2 1

3. Place the mouse cursor over the effects to see what they look like on your page. 4. Click the Play button, at the top right-hand side of your screen.

Adding Element Animation You can animate specific texts and elements present on a page in the same way as you can animate the entire page. To add element animation: 1. Click the text/element you want to animate. 2. Select the Element Animation tab from the sidebar and apply the desired animation effect to your element.

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Now, let us learn about some more features Canva has to offer.

Applying Transparency Applying transparency means making the elements look see-through. In Canva, all elements are fully visible by default. This means that Transparency is set to 100. To apply transparency: 1. Select an element from your design, for example, the boat. 2. Click the Transparency icon appears.

from the options bar above the design area. The Transparency slider

3. Move the slider to the left to decrease the transparency of the boat and to the right to increase the transparency. 4. Observe the effect on the element’s transparency. 2 3

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Using the Copy Style Option Suppose you like the style of an element or a page, such as font, colour, effects, or transparency. You can apply the same styles to other elements or pages as well. To copy and apply a style, follow the given steps: 1. Let’s say, you like the boat for its transparency and want to copy the same to another element. 2. Right-click the boat. A context menu appears. 3. Click the Copy style option. The style is copied. 4. Click the element where you want to apply the copied style. For example, click the mask placed below the word “KERALA”.

The mask becomes transparent with the same transparency value, just like the boat.

Locking Objects Locking an object makes sure that the object remains in its place while you work on the other parts of the design. You can either lock an individual element or the entire page. Chapter 8 • Animations with Canva

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To lock the entire page, select the page and click the Lock page option, as shown in the given image.

To lock the specific elements, right-click the element and select the Lock option from the context menu. You can also click the Lock symbol present on the top bar. The element is locked. Note that another Lock symbol appears near the locked element. To unlock the element, click the Lock symbol again. 2

Discuss!

How can the Lock feature be helpful when you are creating a project?

Do It Yourself 8B Create the designs in Canva, as shown here.

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Explore More!

Wonder how animation works practically?

Do It Yourself 8C 1

Fill in the blanks.

a Page Animation decides how the

will enter the screen.

b To see how your animation looks on an element, you use the c The 2

button.

feature is used to copy the style of an element to another.

Match the following: Task

Icon

When you have completed a design and want no change in it When you want to make the elements look see-through When you want to have the same style as the current element

Points to Remember 1

Canva is a free graphic design platform that is used to create various visual contents, such as graphics, presentations, posters, social media graphics, flyers, and more.

Canva has a wide variety of design templates and tools to choose from for your projects.

Canva offers colourful images, stickers, icons, and shapes as elements that you can easily add to the designs to make them more engaging.

You can also add text to your design using the Text option from the sidebar. You can choose various options for fonts, sizes, and types.

When you add new elements in Canva, they are placed on top of the ones you have already added, creating layers of elements.

You can use the Position option to adjust the layering, alignment, and size of elements.

You can make your designs look interactive by adding animations.

You can use the Copy Style option to copy the style of one element and apply it to other elements.

You can use the Lock option to lock specific elements or the entire page to prevent accidental changes while working on other parts of your design.

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Chapter Checkup A. Fill in the Blanks. Hints

Create a design

Position

Canva is a popular online tool used for creating various types of

To create a design in Canva, you need to click the

Elements in Canva include graphics, stickers, icons, and

The

shapes

visuals .

button. .

option in Canva allows you to control the arrangement of various elements in your design.

B. Tick () the Correct Options. 1

What can layers in Canva NOT be compared to?

a Transparent sheets kept on top of each other

b Jigsaw puzzle

c Layers of paint

d Images put on top of each other

In Canva, what can you add animation effects to?

a Only the text elements

b Only the images

c The entire design

d Only the background colour

What can you do with text animation in Canva?

a Change the font of the text

b Adjust the transparency of the text

c Make the letters move, slide, bounce, or fade

d Convert text into images

What does adjusting transparency in Canva do?

a Changes the font size of the element

b Rotates the element

c Makes a layer see-through

d Duplicates the element

How does the Copy Style feature in Canva help your design?

a It changes the animation effects.

b It applies the same style from

c It duplicates the entire design.

d It adds comments to the design.

one element to another.

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C. Who Am I? 1

I make layers see-through, creating visual effects and overlays.

I can animate elements to slide, bounce, or fade in and out.

I prevent unwanted changes in the project.

I help you position the element at the top, middle, or centre of the design area.

I am used to turn elements around by a desired angle.

D. Write T for True and F for False. 1

Canva is difficult to use and requires professional design skills.

The Layers tab in Canva helps order the elements like a stack.

Locking objects in Canva prevents any changes to that element.

The element will not be visible if the transparency value is 100.

The Forward option brings the layer to the top of the stack.

E. Answer the Following. 1

What is the purpose of the Position option in Canva?

Explain the difference between the Forward/Backward and To Front/To Back arrangement options.

What is animation?

What are layers? Give an example.

Why would you use the Lock option for an object in Canva?

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F. Apply Your Learning. 1

Aleena is making a poster for Diwali. She placed various elements in her design. Which Canva feature can she use to put the elements exactly in the centre?

Archita made a crossword puzzle for her classmates, using Canva. However, she made some adjustments to the project, causing the crossword to become nearly invisible. What do you think she must have done?

Maya is creating a design with lots of elements. She wants some objects to be in front while others hide behind them. Which Canva feature can she use to control the layers and make her design look like a playful scene?

Imagine you are a young chef who wants to share your favourite recipes. You have designed a digital recipe card using Canva. You have created multiple layers of elements in the recipe card. The text of the recipe card is hidden behind the images. What might be the problem?

Rani created a card for her friend’s birthday. She was showing it to her younger brother Anuj. Anuj was very curious and deleted the text in the card by mistake. How could have Rani prevented this mistake?

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Introduction to AI Can you imagine a world where: 

your smartphone understands your commands;



your email accurately filters out spam; and



our car automatically navigates through traffic and parks at the y right spot?

All of this is actually possible with the help of Artificial Intelligence or AI. Artificial Intelligence is the ability of machines to think and act like humans. Therefore, Artificial Intelligence is a branch of computer science that helps to create intelligent machines capable of simulating human-like reasoning, problem-solving, and decision-making.

Explore More!

Want to know more about artificial intelligence? Scan here!

Applications of AI Be it in your classroom or in the marketplace, or at your home, you can find applications of AI everywhere. Some prominent fields where AI has made a significant impact are given as follows: Field

Application

Healthcare

Detecting diseases, discovering new drugs, doing remote surgery

Business

Preventing fraud, helping us shop by giving recommendations

Education

Smart content that helps us learn

Banking

Managing money and bank accounts, preventing fraud

Transport

Autonomous vehicles, ride-hailing apps, navigation system

Social Media

Face recognition, content filtration

Security

Data security, identification of fraud, threats, etc.

Robotics

Heavy industry, robotic surgeries, home assistants

Smart homes

Smart devices and connectivity to mobile applications

Did You Know? In 1997, a computer named “Deep Blue” made by IBM beat the world chess champion, Garry Kasparov. It was the first time a computer won against a champion in chess.

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Domains of AI There are three main domains of AI: Machine Learning: Machine learning is like teaching a computer to learn from experiences. It is used to help computers do smart things on their own. Let us understand this concept with the help of an example: When you teach your pet to recognise your friends, you may reward it every time when it correctly recognises them. Over time, your pet is able to recognise your friends and family more quickly than earlier. Similarly, AI machines also learn from vast datasets, becoming increasingly intelligent over time. Computer Vision: This domain of AI makes the computers ‘see’ and ‘recognise’ objects. For example, just as we see an object and immediately recognise it, similarly the AI machine looks at an object using cameras, and matches it with the thousands and thousands of images in its dataset. If the object matches with the description of the given object, then the machine recognises it. Natural Language Processing: Natural Language Processing or NLP makes the computers understand the human language in text and spoken form. Digital assistants and chatbots use the concept of NLP to interact with humans. In this chapter, you will learn more about NLP. Let’s get started.

Natural Language Processing Have you ever wondered how AI assistants like Alexa or Siri listen to your commands and respond? It is possible with the help of a domain of AI, that is called Natural Language Processing. Imagine a situation where you are talking to a computer or a robot. As it is a machine, it will not be able to understand your language. Here, NLP plays its role. NLP makes the machine understand your language and respond to you in a way that makes sense. NLP helps computers understand us and talk to us like people. To understand the concept of NLP practically, let us create an app which will convert the input text to speech. For this, we will use the MIT App Inventor. This app will process the input text and convert it to speech.

text

AI App based on NLP

So, let’s get started. Chapter 9 • AI—Beyond Reality

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speech

Think and Tell

Imagine you have a computer that has NLP. How would you use it to make your daily life easier or more fun?

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The MIT App Inventor The MIT App Inventor is an online platform for creating apps for mobile phones and tablets. It is a very easy and simple platform to learn app creation and coding. This platform focuses on teaching everyone, especially young children, to create their own apps.

Creating an App The Tekie platform allows you access MIT App Inventor directly. If you are accessing MIT App Inventor directly, follow the steps given. Otherwise jump straight to starting a new project. 1. Visit the following link to open MIT App Inventor: https://appinventor.mit.edu/ 2. The following screen appears:

3. Click on the Create Apps! Button. 4. A sign in screen appears. You can use your Gmail id to login or you can create a new one. 5. After signing in, the Welcome to App Inventor pop-up box appears. Click on the Continue button at the bottom of the screen. 6. Another screen appears, from where you can choose to view the tutorials or you can start a new blank project.

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Click here to start a blank project

Continue Button

Starting a New Project 1. Click on START A BLANK PROJECT. 2. The Project View window appears. 3. A dialog box appears asking to give a project name to your project. 4. Give an appropriate name to your project, for example, text_to_speech and click on OK. 5.

A new project with the same name will be created.

6. Click on it. The Project View window will open.

Sections of the Project View Window The Project View window is divided into four sections: Palette: Various components are present under different categories in the palette. Viewer: You can select any component from the palette and drag and drop it on the screen in the Viewer section. Components: The components section shows the various components that are placed in the Viewer. Properties: The Properties section shows the properties of the selected component. Chapter 9 • AI—Beyond Reality

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Properties Palette

Viewer Components

Working with Palette Section Let us now create the interface of the app. 1. From the Palette section, drag the Button component and place it in the Viewer section on Screen1.

Button 1 added in Components section

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2. You can observe the Button1 component is also added under the Components section. 3. Now in the Properties section, scroll down to the Text property of the button. Replace the text “Text for Button1” with “Text to Speech”.

4. Now, in the Palette section, click on the Media drawer. 5. Select the Text to Speech component and drop it on Screen1. 6. It will not be visible on the screen. However, you can see it below Screen1 as a Non-visible component. The interface of the app is created. Now, let’s create a code for it.

Coding the App The next step is to create a code for the app. To code in MIT App Inventor is very easy and userfriendly. You can create code for your app by using various blocks present in the Blocks Editor.

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To create code for your app, follow the given steps: 1. Click on the Blocks Editor button in the right-hand upper corner of the Project View window. 2. The Blocks Editor will open with the Blocks section on the left and the Viewer section on the right.

3. Click on Screen1 > Button1 from the Blocks pane. 4. The blocks related to Button1 will appear. 5. Drag when Button1.Click block from the Blocks drawer and drop it in the Viewer pane.

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6. Similarly, click on Screen1 > TextToSpeech1. 7. The blocks related to Text to Speech component will appear. 8. From the Blocks drawer, drag the call Text to Speech1.Speak block and drop it inside the when Button1.Click block.

9. Now, from Built-in > Text drawer, drag the “A text string” block and plug it into the socket labelled message. 10. Click inside the text string block and type your desired message. For example, “Welcome to the world of coding!”

11. Your app and its code are ready to use.

Testing the App 1. To test your app, you will need a mobile phone. 2. Go to the Google Play Store of your android phone and download MIT AI2 Companion App. Chapter 9 • AI—Beyond Reality

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3. Install the app by clicking on “Install”. 4. After installation, open the app. You have to provide a six-character code to connect. 5. Now, to get the code, go to your computer where you have created your app.

Explore More!

You can scan this QR Code to get the MIT AI2 Companion App on your mobile phone.

6. Go to the Connect menu and select the AI Companion option. 7. A Connect to Companion window will open with a six-character code.

You can now fill in this six-character code on the mobile phone app. 1. The app will now open on your mobile. 2. Click on the button that you have created. 3. You will be able to hear the message that you have provided in the app code, that is “Welcome to the world of coding!”

Welcome to the world of coding!

4. Keep exploring!

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Points to Remember 1

Artificial Intelligence is the ability of machines to think and act like humans.

Some of the applications of AI are in the fields of healthcare, business, education, banking, transport, social media, security, robotics, and smart homes.

There are three main domains of AI: Machine Learning, Computer Vision, and Natural Language Processing.

Machine learning is like teaching a computer to learn from experiences.

Computer vision makes the computers see and recognise objects.

Natural Language Processing or NLP makes the computers understand the human language in text and spoken form.

MIT App Inventor is an online platform for creating apps for mobile phones and tablets.

The Project View window of MIT App Inventor is divided into four sections, Palette, Viewer, Components, and Properties.

Chapter Checkup A. Fill in the Blanks. Hints

natural language processing

experience

Artificial Intelligence is the ability of machines to think and act like

NLP stands for

Machine Learning is like teaching a computer to learn from

computer vision

humans .

. .

helps computers see and recognise objects.

B. Tick () the Correct Options. 1

What does AI stand for?

a Advanced Intelligence

b Artificial Information

c Artificial Intelligence

d Automated Invention

Which domain of AI focuses on teaching computers through experience?

a Computer Vision

b Natural Language Processing

c Machine Learning

d Deep Learning

What is the main purpose of Natural Language Processing?

a To make computers understand human language

b To create virtual reality games

c To design mobile apps

d To analyse images

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Which of the following is NOT an application of AI?

a Predicting the weather

b Detecting diseases in healthcare

c Personalised shopping recommendations

d None of these

C. Who Am I? 1

I am a branch of computer science that enables machines to simulate human-like reasoning, problem-solving, and decision-making.

I am a domain of AI that help computers do smart things on their own.

I am often used by digital assistants and chatbots.

I am an online platform that makes it easy for people, especially young children, to create their own mobile apps.

D. Write T for True and F for False. 1

Artificial Intelligence refers to the artificial intelligence of humans.

Natural language processing makes computers understand human language only in written form.

Machine learning involves teaching computers using experiences.

Computer vision allows computers to recognise objects through touch.

E. Answer the Following. 1

What are the three main domains of AI mentioned in the chapter?

How does Machine Learning work? Give an example.

Describe the concept of Computer Vision and provide an example.

Explain how Natural Language Processing (NLP) makes computers understand human language.

What is the purpose of the MIT App Inventor?

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F. Apply Your Learning. 1

Amitesh is a healthcare professional. Explain to him how he can make use of AI in the healthcare field.

Sharvi is creating a project in which she wants to create a code for the computer to recognise things. Which domain of AI will she be using to create this project?

Nimisha owns a pet cat. She is training her to recognise various objects in her room. Which domain of AI learns in a similar manner?

Rudra wants to create a personalised app for his business. Which application would you suggest that he use?

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Computer Science

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