The Design of Everyday Things
Donald A. Norman
Principles of Good Design ●
Visibility
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Conceptual model
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Mappings.
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Feedback
Visibility
Visibility
Visibility
Visibility
Visibility
Conceptual Model
Conceptual Model
Affordances
Affordances provide strong clues to the operations of things. User knows what to do just by looking. No label, picture or instruction is required When simple things need pictures, labels or instructions, the design has failed.
Affordances
Affordances Plates for pushing Knobs for turning Slot for inserting
Affordances
Affordances
Mapping
Natural Mapping
Feedback â—?
Give each action an immediate and obvious effect
Feedback Using Sound for Visibility ●
The click when the bolt on a door slides home
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The “zzz” sound when zipper work properly
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The “tiny” sound when a door doesn't shut right
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The roaring sound when a car muffler gets a hole
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The rattle when things aren't secured
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The whistle of a tea kettle when the water boils
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The click when the toast pops up
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The increase in pitch when a vacuum cleaner get clogged
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The indescribable change in sound when a complex piece of machinery starts to have problems
Knowledge in The Head Knowledge in The World
Knowledge in The World
Knowledge in The Head
Knowing What To Do ●
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Which parts move; which are fixed? Where should the object be grasped? What part is to be manipulated? What is to be held? Where is the hand to be inserted? If it is speech sensitive, where does one talk? What kind of movement is possible: pushing, pulling, turning, rotating, touching, stroking? What are the relevant physical characteristics of the movement? With how great a force must the object be manipulated? How far can it be expected to move? How can success be gauged? What parts of the object are supporting surfaces? How much size and weight will the object support?
Principles of Good Design ●
Visibility By looking user can tell the state of the device and alternative for action
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A good conceptual model The designer provides a good conceptual model for user, with consistency in the presentation of operation and results and a coherent, consistent system image.
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Good mappings. It is possible to determine the relationships between actions and results, between the controls and their effects, and between the system state and what is visible
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Feedback The user receives full and continuous feedback about the result of actions
How Easily Can One: ● ●
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Determine The Function of the Device? Tell What Actions are Possible? Determine Mapping from Intention to Physical Movement? Perform the Action?
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Tell if System is in Desired State? Determine Mapping from System State to Interpretation? Tell What State the System is in?