A gearbox is a mechanical device that transmits power from an engine to the wheels of a vehicle. It adjusts the torque and speed of the engine's output, allowing the vehicle to operate efficiently at various speeds. Gearboxes are commonly found in cars, trucks, and other machinery, and they can be either manual or automatic, depending on how the driver interacts with them. In a manual gearbox, the driver uses a clutch pedal and gear stick to change gears, while an automatic gearbox shifts gears automatically based on speed and load. Gearboxes are essential for optimizing performance and fuel efficiency in vehicles, making them a crucial component in automotive engineering and design.