The Google Search Engine
Google's search engine is a powerful tool. Without search engines like Google, it would be practically impossible to find the information you need when you browse the Web. Like all search engines, Google uses a special algorithm to generate search results. While Google shares general facts about its algorithm, the specifics are a company secret. This helps Google remain competitive with other search engines on the Web and reduces the chance of someone finding out how to abuse the system.
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A Web page’s PageRank depends on a few factors: Google uses automated programs called spiders or crawlers, just like most search engines. Also like other search engines, Google has a large index of keywords and where those words can be found. What sets Google apart is how it ranks search results, which in turn determines the order Google displays results on its search engine results page (SERP). Google uses a trademarked algorithm called PageRank, which assigns each Web page a relevancy score.
The frequency and location of keywords within the Web page: If the keyword only appears once within the body of a page, it will receive a low score for that keyword.
How long the Web page has existed: People create new Web pages every day, and not all of them stick around for long. Google places more value on pages with an established history.
The number of other Web pages that link to the page in question: Google looks at how many Web pages link to a particular site to determine its relevance.
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Out of these three factors, the third is the most important. It’s easier to understand it with an example. Let’s look at a search for the terms “Planet Earth.” As more Web pages link to Discovery’s Planet Earth page, the Discovery page’s rank increases. When Discovery’s page ranks higher than other pages, it shows up at the top of the Google search results page. Because Google looks at links to a Web page as a vote, it’s not easy to cheat the system. The best way to make sure your Web page is high up on Google’s search results is to provide great content so that people will link back to your page. The more links your page gets, the higher its PageRank score will be. If you attract the attention of sites with a high PageRank score, your score will grow faster.
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Google initiated an experiment with its search engine in 2008. For the first time, Google is allowing a group of beta testers to change the ranking order of search results. In this experiment, beta testers can promote or demote search results and tailor their search experience so that it’s more personally relevant. Google executives say there’s no guarantee that the company will ever implement this feature into the search engine globally.
with search engines. With many of its services, Google has entered into direct competition with other companies. Google’s specialized searches are an extension of its normal search engine protocol. With specialized searches, you can narrow your search to specific resources. You can enter keywords into Google and search for:
As Google has grown, the company has added several new services for its users. Some of the services are designed to help make Web searches more efficient and relevant, while others seem to have little in common
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Images relating to key words Maps News articles or footage Products or services you can purchase online
For these searches, Google has created specialized indexes that only contain relevant sources. For example, if you search for the term “Planet Earth” in the news category, the results will include only news articles that contain those keywords. The results will look very different from Google’s normal SERP.
Blog entries containing the keywords you’ve chosen Content in books Videos Scholarly papers
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In the last few years, Google has unveiled services that don’t relate to search engines upon first glance. For example, Google’s Gmail is a free Web-based e-mail program. When the service first launched, Google limited the number of users who could create accounts. The first group of users could invite a limited number of people to join the service, and so Gmail invitations became a commodity. Today, anyone can sign up for a free Gmail account. Gmail organizes e-mails into conversations. This means that when you send an e-mail to someone and he or she replies, both e-mails are grouped together as a thread in your inbox. This makes it easier to follow the flow of an e-mail exchange. If you reply to your friend’s response, Google will attach your message to the bottom of the thread. It’s easy to navigate through the e-mail program and follow specific conversations.
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Another free service from Google is Google Docs, a storage database and collaborative productivity software suite. It includes word processing, spreadsheet and presentation programs. Creating a Docs account is free and allows you to store up to 5,000 documents and images online. Each document can be up to 500 kilobytes, and each embedded image can be up to 2 megabytes. You can share documents on Google Docs, which allows your friends to view and make changes alter the documents. You can also store all of your documents on Google’s servers and access them wherever there’s an Internet connection.
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You can perform a Google search with any short message service (SMS) compatible cell phone, even if you can’t access the Web with your phone. Simply text your query to 466453 (which spells GOOGLE on a phone pad). Google will send a response back within a couple of seconds. With an advanced search, you can use Google to retrieve the most relevant results for your keywords. You can search for documents written in a specific language or saved in a particular file format like .pdf or .rtf. You can tell Google where to look for the keywords, such as in page titles or headers. Google even allows you to limit searches to a single domain name. Try typing in “site:howstuffworks. com ‘cloud computing’” in the Google search bar to see how it works. Each choice you make tells Google which index to use when returning your search results.
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