System Quality Attributes are characteristics that define how well a system performs its intended functions. These attributes include performance, reliability, scalability, and security. They help stakeholders assess the system's effectiveness and efficiency, ensuring it meets user needs and expectations. These attributes are crucial during the design and evaluation phases of a system's lifecycle. For instance, usability focuses on how easy the system is for users to interact with, while maintainability refers to how easily the system can be updated or repaired. Together, these attributes guide developers in creating robust and user-friendly systems.