Answer: Clutches are used in many different devices, not just vehicles. Clutches are used in any device that has two or more rotating shafts. Usually, an engine drives one of the shafts and the other shaft, powered by the first shaft, will drive a separate part. For instance, in a vehicle, the engine is constantly turning and when in contact with the transmission, the vehicle’s wheels turn. Clutches are used to separate the engine from the transmission. When you want to stop or slow down in a manual transmission vehicle, the clutch must be engaged in order to keep your engine running. Now, to understand what may go wrong with a clutch, it is important to understand how a clutch really works. Clutches operate by using friction to keep your engine and transmission connected. This friction is created between a clutch plate, which connects to the transmission, and a flywheel, which connects to the engine. When your clutch pedal is not engaged, your clutch contains springs that force a pressure plate to press the clutch plate into the flywheel creating the necessary amount of friction force to keep the engine and transmission connected. When this happens, your engine and transmission spin at the same rate. Then, when you do engage your clutch pedal, a cable or hydraulic piston pushes on the clutch’s release fork to release the springs. When this happens, the pressure plate pulls away and the clutch plate separates from the flywheel. Again, when this occurs, your engine and transmission are now separated. During a clutch replacement service, the clutch plate, which is covered with a friction material, and the pressure plate are replaced. During this service, depending on what type of clutch you have, your cable or hydraulic system will also be checked. Your clutch pedal will also be checked. The pedal’s free play distance will be examined and adjusted if necessary (there should be an inc h or two of free play before the clutch is actually engaged).