Cam Shaft

A Cam Shaft LH and RH has one or more Cams attached to it.
This is generally connected to the Piston which transmits the power.
The power is produced by the internal combustion engine.
Some engines rely on a single Camshaft per cylinder bank, which is known as a single overhead Camshaft (SOHC).
Most engines are driven by a two Camshafts per cylinder bank arrangement (one camshaft for the intake valves and another for the exhaust valves) such Camshaft arrangement is known as a double or dual overhead CAM (DOHC).
Thus, a V engine, which has two separate cylinder banks, may have four Camshafts (colloquially known as a quad-cam engine).