A pump moves a fluid. A water supply for irrigation or consumption is a necessity for everybody. This explains the age of the first pump, invented over 5000 years ago in Mesopotamia and Asia.
There are many models of pumps. This animation illustrates the principle of an old hand pump. The Greek, Ctesibius invented the first hydraulic machines (third century BC.).
A valve system is articulated to create a depression in one compartment and/or an overpressure in another. To increase the flow, the movement back and forth may be provided by a motor.