What does the term 'usability testing' evaluate?

Usability testing specifically focuses on assessing how easy and satisfying a software application is for users to operate. This type of testing aims to gather qualitative and quantitative data from real users interacting with the system, which helps to ensure that the software meets user expectations and can be used effectively without unnecessary difficulty.

The evaluation process typically involves observing users as they try to complete tasks with the software, collecting feedback on their experiences, and identifying any areas where users may struggle. Key metrics often include user satisfaction, ease of navigation, and how intuitive the interface appears to users. By focusing on these aspects, usability testing ultimately aims to enhance the overall user experience and ensure that the product is user-friendly.

The other options relate to different types of testing such as performance testing (evaluating load capacity), code efficiency (focusing on the software's internal structure and speed), and reliability across environments (assessing how well the software operates under various conditions). Each of these areas is important for overall software quality but does not fall under the scope of usability testing.