What is a User Interface?  Everything in a device with which a human being interacts.  The total “user experience”  Not necessarily tied to computers –Doors –Thermostat –VCR

User Interface Examples  Your car –Pedals, steering wheel, gearshift…  Altair (from videos) –Knobs, switches, blinking lights…  Microsoft Windows –Mouse, keyboard, Start button…

Computer User Interfaces  Webopedia.com*:  “An interface is a set of commands or menus through which a user communicates with a program. A command-driven interface is one in which you enter commands. A menu-driven interface is one in which you select command choices from various menus displayed on the screen.” From part of internet.com Corp., copyright

Advantages of Good User Interface Design  Ease of use  Visually appealing  Shorter learning curve  $$$ –Designer sells more products –User is more efficient / productive

8 Golden Principles* 1. Strive for Consistency 2. Include shortcuts 3. Offer informative feedback 4. Design dialogs to yield closure From Schneiderman, Ben, Designing the User Interface, Addison-Wesley, 1998.

8 Golden Principles 5. Offer error prevention and simple error handling 6. Permit easy reversal of actions 7. Keep user in control 8. Reduce short-term memory load

User Interface Exercise  In groups of 4 – 5: –Pick one of the following applications  Word, Mozilla, Excel –Give 2 good and 2 bad characteristics of its user interface –Do any other principles of good user interface design come to mind?

Applications vs. Web  Previous slides focused on applications  Assumed that principles held for Web pages, too – so most Web pages designed with them in mind.  Spool, et. al. showed that this might not be the best way…

Applications vs. Web  Applications are tools –Ease-of-use means the tool is easy to manipulate – easy to get it to do what you want.  Web pages are information sources –Ease-of-use means easy to find the information you are looking for  However, rules derived from print layout may not be useful either

‘Usable’ Web Pages  Some good characteristics: –Descriptive Links –Minimize Animation –Readability vs. Scanability  Information retrieval vs. Surfing