The clutch allows power from the engine to be transferred to the gear box, when you press the clutch all the floor power is disrupted between the engine and the transmission and it allows you to select a different gear, or select neutral if you at a stop. If the clutch disc wears the engine will race up but power may not be transferred to the transmission and the vehicle may eventually not even move. If the clutch is "slipping" it is normally accompanied by bad smell.
If my clutch is slipping, can I simply get my clutch adjusted, or must it be replaced? (95 VW Jetta 2.0L Manual). Thank you, -B.H.