In this lecture on Practical & Lab Demonstration: Friction Stir Welding, we explore the fundamentals and application of the FSW process. The session covers FSW machines (conventional and CNC), the welding tool, stages of the process, and common terminology. A live demonstration of friction stir welding is included, followed by a study of how process parameters affect joint characteristics. The lecture also examines the macrostructure, microstructure, and mechanical properties of the welded joint.