Usability

can be broken down into the following goals:

  • Effectiveness – How accurately and completely users can
    accomplish tasks
  • Efficiency – How quickly users can complete tasks
  • Safety – Avoid dangerous situations caused by interaction with
    technology
  • Utility – Provide enough functionality for users to accomplish
    necessary tasks
  • Learnability – How easy is it to learn to use technology
  • Memorability – How easy is it to remember how to use a
    technology once you have learned how to use it