The manual transmission clutch is a device used to connect and disconnect engine power flow to the transmission at the will of the driver. A driver operates the clutch with a clutch pedal inside the vehicle. This pedal allows engine power flow to be gradually applied when the vehicle is starting out from rest and interrupts power flow to avoid gear clashing when shifting gears.

Engagement of the clutch allows for power transfer from the engine to the transmission and eventually to the drive wheels. Disengagement of the clutch provides the necessary halt of power transfer that allows the engine to continue running while no power is supplied to the drive wheels.

Engagement and disengagement of the clutch is controlled by a pedal and clutch linkage that must be properly adjusted. The machined surfaces of the flywheel and pressure plate must be flat and free of cracks and scores in order to adequately clamp the clutch disc. Clutch slippage, vibration, and noise are minimised by the proper alignment of engine and transmission/transaxle and of the clutch components.