Five Aspects of Usability

Jakob Nielsen suggests that there are five aspects of usability:

• Ease of learning: the interface needs to allow users who have never seen it before to learn to use it quickly to succeed in accomplishing basic task
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• Efficiency of use: the interface needs to be designed to allow rapid accomplishment of tasks for more experienced users
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• Memorability: casual users of the site are assisted by an interface design that they can remember how to use
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• Error frequency and severity: the interface should be designed to minimize the number and severity of errors, and allow for quick error recovery
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• Subjective satisfaction: the experience of using a web interface should be a pleasant one