Usability refers to how effectively specified users can use a system to achieve their goals in a given context. It measures the ease of use and user satisfaction with a product or service.
Key Aspects:
- Learnability: How easy it is for users to accomplish tasks initially.
- Efficiency: The speed at which users can perform tasks once familiar.
- Memorability: How easily users can re-establish proficiency after a period of not using the system.
- Error Rate: The frequency of errors users make while interacting with the system.
High usability leads to better user experiences and increased user satisfaction.