Pump head refers to the usable power transferred to pumped fluid when it is pumped against gravity. Head (H) is given in meters. It is not the same as system head.
Put simply, head describes how much kinetic energy is needed for the pump to produce enough pressure to transport the fluid from the suction nozzle to the discharge nozzle. It is dependent on static pressure, flow rate and geodetic head – i.e. the difference in height between the suction and discharge nozzles of the pump.
Alongside power and delivery rate, head is one of the most important criteria to consider when selecting a pump, especially for centrifugal pumps. Another important metric is optimum head. It describes the total head of a pump when operating at optimum efficiency.