The clutch and related components are part of a standard shift transmission.   The clutch system is designed to disengage the engine torque so the manual transmission can change gears.   In the photo are three components that work together to achieve the disengagement and engagement of the engine torque.   The clutch disc has a friction material on it that is designed to wear.   The disc is located between the flywheel and the pressure plate.   When the clutch pedal is pushed down the spring loaded fingers on the pressure plate pull the pressure plate away from the clutch disc disengaging the engine torque.   Releasing the clutch pedal engages the torque of the engine by putting pressure on the disc against the flywheel.   The flywheel is attached to the engine. Warning signs of a clutch failure are vibration when releasing the clutch pedal in first gear.   A clutch pedal that doesn't engage until the pedal is near the end of it stroke.   Grinding noise when changing gears or difficulty shifting gears.