The JSF Lifecycle is a series of phases that a JavaServer Faces application goes through to process user requests and render responses. It consists of six main phases: Restore View, Apply Request Values, Process Validations, Update Model Values, Invoke Application, and Render Response. Each phase has a specific role in managing the state of the application and handling user interactions. During the Restore View phase, the framework retrieves the previous view state. In the Apply Request Values phase, user input is processed, followed by Process Validations to ensure data integrity. The Update Model Values phase updates the application’s data model, while Invoke Application executes any application logic. Finally, the Render Response phase generates the final output to the user.