Performance Testing is a non-functional testing process that measures system performance under a particular load. Coursera's Performance Testing catalogue teaches you how to evaluate, predict, and validate the speed, stability, and scalability of a system. You'll learn how to plan, design, and execute tests that assess system capacity, identify bottlenecks, evaluate performance criteria, and ensure system robustness. This skill is crucial for software engineers, QA analysts, and IT professionals aiming to ensure their applications can handle real-world demands and deliver a seamless user experience.