A Flight Management System (FMS) is an onboard computer system that helps pilots navigate and manage a flight. It integrates various functions, such as flight planning, navigation, and performance calculations, allowing for smoother and more efficient operations. By automating many tasks, the FMS reduces the workload for pilots, enabling them to focus on flying the aircraft safely. The FMS uses data from multiple sources, including GPS, inertial navigation systems, and air traffic control, to provide real-time information about the aircraft's position and route. This system not only enhances safety but also optimizes fuel efficiency and flight time, making air travel more reliable and economical.