Selenium with Core Java, Cucumber, REST Assured, and Jenkins is a comprehensive test automation stack commonly used for end-to-end testing of web applications, including their user interfaces and APIs (Application Programming Interfaces). Each component in this stack serves a specific purpose in the automated testing process. Together, Selenium with Core Java, Cucumber, REST Assured, and Jenkins create a powerful test automation ecosystem that supports the efficient testing and validation of web applications throughout the development lifecycle.