The mechanical power can be generated in various ways, and electrical as well as pneumatic systems are alternatives to hydraulic power generation systems. Mechanical power is used in a variety of applications such as pumps, motors and valves.

The pump converts a small amount of mechanical power into hydraulic power, the valve controls the hydraulic oil flow and the hydraulic cylinder converts the hydraulic power into a large amount of mechanical power.  The main components of a typical basic hydraulic system are a pump, a valve and a hydraulic cylinder. The hydraulic oil becomes hot during operation.