Usability: a brief introduction

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A presentation I gave at BT, minus one BT-specific slide.

Published in: Technology, Design

Usability: a brief introduction

  1. 1. Usability A brief introduction Philip Morton http://www.flickr.com/photos/david_nicholai/987226801/
  2. 2. <ul><li>What is usability? </li></ul><ul><li>Why is it important? </li></ul><ul><li>How does bad usability come about? </li></ul><ul><li>How can you improve it? </li></ul><ul><li>Further reading </li></ul><ul><li>Questions </li></ul>Outline
  3. 3. What is usability? Usability is two things: <ul><li>A measure of how easy user interfaces are to use. </li></ul><ul><li>The methods for improving ease-of-use during the design process. </li></ul>Usability is two things: In other words, how people interact with the systems and objects around them.
  4. 4. What is usability? Usability is all around us:
  5. 5. What is usability? Usability is all around us:
  6. 6. What is usability? Usability is all around us:
  7. 7. What is usability? Usability is all around us: http://www.flickr.com/photos/96854970@N00/3320024073
  8. 8. What is usability? Usability is all around us: http://www.flickr.com/photos/caddick/471212949
  9. 9. <ul><li>Learning : How easy is it for people to accomplish basic tasks the first time they encounter a system? </li></ul><ul><li>Efficiency : Once people have learnt the design, how quickly can they perform tasks? </li></ul><ul><li>Memory : When people return to the system after a period of not using it, how easily can they re-establish proficiency? </li></ul><ul><li>Errors : How many errors do people make, how severe are these errors, and how easily can they recover from the errors? </li></ul><ul><li>Satisfaction : How pleasant is it to use the system? </li></ul>What is usability? Usability has five core components: http://www.useit.com/alertbox/20030825.html
  10. 10. <ul><li>People will go to great lengths to avoid using difficult systems. </li></ul><ul><li>If they have to use a difficult system, they will do so as little as possible. </li></ul><ul><li>If they have to use a difficult system, they will waste time. </li></ul><ul><li>More support will be necessary. </li></ul><ul><li>More changes will be necessary. </li></ul>Why is usability important? Bad usability costs money: In the same way, good usability can make money.
  11. 11. Why is usability important? Bad usability can cost lives. What’s the largest threat to a nuclear power station?
  12. 12. <ul><li>Three Mile Island, 28 th March 1979. </li></ul><ul><li>A mechanical fault caused a cooling system valve to stay open. </li></ul><ul><li>A light in the control room indicated that power to open the valve was off. </li></ul><ul><li>Engineers assumed that the valve was closed, when it was still open. </li></ul><ul><li>The problem was not discovered for hours. </li></ul><ul><li>Coolant leaked from the reactor. </li></ul><ul><li>Caused a partial core meltdown. </li></ul><ul><li>This is a bad thing. </li></ul>Why is usability important? Bad usability can cost lives.
  13. 13. How does bad usability come about? A lack of communication between everyone involved in building the system.
  14. 15. <ul><li>We can’t remember everything. </li></ul>How does bad usability come about? Not understanding how people really use systems:
  15. 16. <ul><li>Our mental model of a how a system works is often not the same as reality. </li></ul>How does bad usability come about? Not understanding how people really use systems:
  16. 17. <ul><li>We don’t make logical decisions; we choose the first reasonable option. </li></ul><ul><li>Everyone makes mistakes, even experts. </li></ul>How does bad usability come about? Not understanding how people really use systems:
  17. 18. How does bad usability come about? Not understanding how the design process works.
  18. 19. How can you improve usability? Don’t listen to people. “ To design an easy-to-use interface, pay attention to what users do, not what they say. Self-reported claims are unreliable, as are user speculations about future behaviour.” – Jakob Nielsen http://www.useit.com/alertbox/20010805.html Observe them.
  19. 20. <ul><li>Frequent, formal usability testing is best. </li></ul><ul><li>If you can’t get or afford this, a few colleagues will do. You don’t need many of them: </li></ul>How can you improve usability? http://www.useit.com/alertbox/20000319.html Don’t listen to people. Observe them.
  20. 21. <ul><li>Keep it simple. </li></ul>How can you improve usability? Avoid complexity and the paradox of choice: http://www.bt.com
  21. 22. <ul><li>Expose other options only when relevant. </li></ul>How can you improve usability? Avoid complexity and the paradox of choice: http://www.gmail.com
  22. 23. <ul><li>Provide people with constraints. </li></ul>How can you improve usability? Avoid complexity and the paradox of choice: http://www.kayak.com
  23. 24. <ul><li>Removed extraneous text and options. </li></ul>How can you improve usability? Avoid complexity and the paradox of choice: http://www.paypal.com
  24. 25. How can you improve usability? Provide people with feedback. http://www.kayak.com http://www.gmail.com http://www.twitter.com http://www.flickr.com
  25. 26. How can you improve usability? Show people the state of the system. http://www.amazon.co.uk http://www.flickr.com http://www.itunes.com
  26. 27. How can you improve usability? Allow people to easily recover from errors. http://www.gmail.com http://www.flickr.com
  27. 28. <ul><li>Usability concerns every object and system. </li></ul><ul><li>Bad usability can be expensive and dangerous. </li></ul><ul><li>Don’t listen to people. Observe them. </li></ul><ul><li>You don’t need a lot of money or people to do usability testing. </li></ul><ul><li>Usability is easy to improve. </li></ul>Summary Key points:
  28. 29. <ul><li>Don’t Make Me Think! by Steve Krug </li></ul>Further reading Books:
  29. 30. <ul><li>The Design of Everyday Things by Don Norman </li></ul>Further reading Books:
  30. 31. <ul><li>useit.com – Jakob Neilsen </li></ul><ul><li>AListApart.com </li></ul><ul><li>BoxesAndArrows.com </li></ul><ul><li>UXMag.com </li></ul><ul><li>UXMatters.com </li></ul>Further reading Websites:
  31. 32. Questions? http://www.flickr.com/photos/nzdave/491410298/

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