Regression Testing is a type of software testing that ensures that previously developed and tested software still performs as expected after changes or modifications. Coursera's Regression Testing catalogue teaches you the importance of this testing methodology in maintaining software stability and quality. You'll learn concepts like identifying the scope of regression tests, creating regression test plans, and executing them effectively. You'll also understand how to use automation tools for regression testing, manage regression test suites, and integrate regression testing into a continuous integration pipeline. This essential skill set will equip you to contribute to the overall quality assurance process in software development and deployment.