What does non-functional testing assess?

Non-functional testing specifically focuses on evaluating the attributes and characteristics of a system that are not directly related to its specific functionality. These attributes are often referred to as "non-functional requirements," which include aspects such as performance, reliability, usability, and security.

This type of testing is crucial because it helps ensure that a system not only meets the functional specifications but also performs well under various conditions, is secure against potential threats, is user-friendly, and can maintain its reliability over time. For instance, assessing system performance involves checking how quickly it processes requests, while usability testing ensures that the system can be easily navigated by users.

In contrast, other options are focused either on functional aspects or specific design elements that do not encompass the broader categories of non-functional requirements. For example, assessing analytical capabilities relates to how a system processes and analyzes data (a functional requirement), while evaluating the graphical user interface concerns the design and layout—again, a different focus than non-functional testing. Understanding system performance under load might seem related but is just one aspect of a broader category; non-functional testing includes this aspect along with many others like security and reliability. This comprehensive approach ensures that all essential performance metrics are validated for optimal user experience and system integrity.