Goals of Human-Computer Interaction
- Create usable software-enabled products
- Enhance the usability of existing products
- Identify problems and tasks (such as in the workplace) that
can be addressed with software products
Dimensions of usability
Preece, Rogers and Sharp provide one of the more comprehensive lists for
defining usability (p. 14):
- Effectiveness (very general concept, too vague)
- Efficiency (alt term: ease of use)
- Utility (alt term: usefulness)
- Learnability (alt term: ease of learning)
Safety and memorability do
not appear on many people's lists. Effectiveness seems to be
one of the most abused usability terms.
Most authors also include user satisfaction as an
important usability goal (also called attitude or
likeability). Note that Preece, Rogers and Sharp
cover this dimension under User Experience Goals in
HCI practitioners need to be mindful of other practical
considerations when designing their products. These include the
impact of legacy systems, portability and reliability.
Elementary design principles
The text lists some basic design principles that help support the
usability goals listed above. This is a very basic list:
Many of these principles are addressed in Nielsen's heuristic
evaluation (see section 1.6.1 in the text).
- What are examples of software-enabled interactive products?
- What are examples of tasks that have been automated by
software products? How has technology changed the nature of
- Identify products with usability problems. To which
usability objectives (i.e. learnability, efficiency, etc.) do
the problems correspond?
- Often usability objectives have inherent tradeoffs. What
are examples? For example, in which situations might improving
learnability negatively affect efficiency?
- How do the listed design principles support usability goals?
Do some design principles support particular goals?
Last modified: Wed Sep 08 14:43:52 Central Daylight Time 2004