1. Introduction to
Design Principles
Based on Don Norman’s book
“The Design of Everyday Things”
Michael Rawlins, Director, Interaction Design & Strategy
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2. Why me?
• I’m very curious…
• I understand multiple disciplines.
• Bad user experiences bother me.
• I have passion for solving problems.
• I’m intrigued by how different we
Michael Rawlins
Interaction Designer all are as people…
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3. About Don Norman
• A cognitive scientist and engineer who pioneered concepts
related to user centered design.
• Worked at Apple & HP. Now @ NNG (http://www.nngroup.com)
• Examines everyday things as examples of problematic
designs.
• Established Design Principles as a framework for
discussing and thinking about interaction problems.
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4. Design Principles
• Visibility - can I see the interaction?
• Feedback - what’s the object or device doing right now?
• Affordance - how do I use it?
• Mapping - where am I & where can I go?
• Constraints - why can’t I do that?
• Consistency - is this familiar?
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5. Visibility
• Can you see the state of the device
& possible actions?
• Are the controls positioned in a
manner where they can easily be
found and used?
• Problems arise when users can’t see
how to use the device.
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6. Poor Visibility
• Which controls are ambiguous?
• How does this device turn off?
• Which controls have meanings that
are unclear?.
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7. Better Visibility
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8. Feedback
• What is the device doing right now?
• What action is being performed?
Feedback is often multi-sensory
(an audible click and a visual clue of interaction)
How does this work?
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9. Affordance
• Perceived and actual properties of an object that provides
clues to its operation.
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10. Poor Affordance?
• What’s clickable below?
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11. Better Affordance…
• Why do these examples have
better visual affordance?
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12. Mapping
• The relationship between controls and
their effect.
• Do these devices work with each
other?
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13. Mapping
• Problematic examples (what’s good and what’s bad?)
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14. Constraints
• Restricting the kind of actions a user
can take.
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15. Constraints
• How is the users attention
directed to notice the
system constraints?
• What other constraints
should the user notice?
• How does users safety
impact the design of this
gas pump?
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16. Consistency
• Design interfaces to have
similar operations & use
similar elements for achieving
like tasks.
• Similarity increases
learnability.
• Design to aid prior system
knowledge - and aid the users
short and long-term memory.
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17. Consistency
Four types of consistency:
• Aesthetic - style & appearance is repeated to enhance
recognition.
• Functional - meaning and action is consistent to reinforce
learnability and understanding.
• Internal - indicates a system is planned & well thought out
(cultivates trust and user orientation).
• External - establishing an ecosystem & consistency with
other elements in the environment.
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18. Conclusion…
Design Principles are validated by usability methods:
• Learnability - how easy is it to perform basic tasks upon the
users first encounter with the device or interface.
• Efficiency - once the users are familiar with the interface, how
quickly and effectively can they perform tasks.
• Memorability - when users return after not having used the
system, how quickly can they reestablish proficiency?
• Errors - how many errors do users make? How severe are the
errors? Can the users easily recover from errors?
• Satisfaction - how pleasant and effective is the user experience?
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19. Further Reading…
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20. Thank You…
Credit to David Gelb 20