Home Usability Basics Defining Usability

Usability measures how well designed (from the users point of view) an interactive system is. An interactive system can be any product that provides an user interface: e.g. websites, software application, mobile phones or any user-operated devices.

Several factors affect the usability of a system:

• Ease of Learning: How fast can a user learn the systems relevant functions?
• Efficiency: How fast can a user solve tasks with the help of the system?
• Memorability: How easy is it to remember enough to use the system after a certain time period again.
• Error frequency: How often do errors occur? How easy is it to recover from them?
• Subjective Satisfaction: How much does the user like or dislike the system?