What is Usability?
Usability refers to how usable a product is by the intended user.
Usability is defined by five
- Learnability: How easy is it for users to accomplish basic tasks the first time they encounter the design?
- Efficiency: Once users have learned the design, how quickly can they perform tasks?
- Memorability: When users return to the design after a period of not using it, how easily can they reestablish proficiency?
- Errors: How many errors do users make, how severe are these errors,
and how easily can they recover from the errors?
- Satisfaction: How pleasant is it to use the design?
There are many other important quality attributes. A key one is utility, which refers to the design's functionality: Does it do what users need? Usability and utility are equally important: It matters little that something is easy if it's not what you want. It's also no good if the system can hypothetically do what you want, but you can't make it happen because the user interface is too difficult. To study a design's utility, you can use the same user research methods that improve usability.
How Do We Improve a Web Site's Usability?
User testing should be done during product development so results from the testing can be incorporated into the product. Depending on the stage of the design process and the aspect of usability you want to focus on there are different techniques
· Usability testing
o Guide to Planning and Conducting Usability Testing (from University of Washington Libraries) http://www.lib.washington.edu/usability/guidelines/usability-guidelines.html
o Seven Common Usability Testing Mistakes http://www.uie.com/articles/usability_testing_mistakes/
· Focus groups
· Card sorting