Functional Testing is a type of software testing that focuses on checking software against its design specifications to ensure it meets user requirements. Coursera's Functional Testing catalogue equips you with the knowledge to understand, design, and run functional tests on software applications. You'll learn about the various stages of functional testing, including unit testing, integration testing, system testing, and user acceptance testing. You'll also learn to use different testing tools and techniques, how to report issues effectively, and how to contribute to improving software quality. By the end of your studies, you'll have the skills to perform functional testing in any software development lifecycle, thereby enhancing the reliability and performance of software systems.