Engine Horsepower

Horsepower (hp or HP or Hp) is the name of several non-SI units of power. It was originally defined to allow the output of steam engines to be measured and compared with the power output of draft horses. The horsepower was widely adopted to measure the output of piston engines, turbines, electric motors and other machinery. Different regions adopted different definitions of the unit. Most countries now use the SI unit watt for measurement of power.