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The point of this activity is to start thinking about what it means for an interface to be usable. At right is a familiar user interface design:

List some of the aspects of this design that have good usability, and some that have poor usability. Think about the aspects of usability we've discussed (learnability, memorability, efficiency, errors, satisfaction), and write down which aspect(s) of usability are involved in each good or bad point you cite.