A flight management system (FMS) is an onboard computer system that automates various tasks related to flight planning and navigation. It helps pilots manage the flight path, fuel consumption, and other critical parameters by integrating data from multiple sources, such as GPS and inertial navigation systems. The FMS allows for efficient route planning and can adjust the flight path in real-time based on changing conditions. The FMS typically includes a control display unit (CDU) where pilots input data and receive information about the flight. It also interfaces with other systems, such as autopilot and weather radar, to enhance safety and efficiency during flight. Overall, the FMS plays a crucial role in modern aviation, improving operational performance and reducing pilot workload.