We saw the philosophical angle to various dimensions of usability in previous blog posts, with several examples. This series will focus on the practical dimensions – another, deeper view of the characteristics of usability: Whitney Quesenbery’s Five Es of Usability. With examples, of course.
ISO 9241 defines usability as:
The effectiveness, efficiency and satisfaction with which specified users achieve specified goals in particular environments.
effectiveness: the accuracy and completeness with which specified users can achieve specified goals in particular environments; efficiency: the resources expended in relation to the accuracy and completeness of goals achieved; satisfaction: the comfort and acceptability of the work system to its users and other people affected by its use.
Extending the concept, and narrowing it down to fundamental elements, experts suggest the following five characteristics that are necessary to be met for the users of a product or a web site:
- Error Tolerant
- Easy to Learn
Watch this space as we dig into each individual ‘E’ with some relevant examples.