PS stands for PferdStarke, which is German for "horse strength" and is the metric measure of horsepower. It is used to describe the power of a cars engine, similar to horsepower (HP) and brake horsepower (BHP). One PS is equal to about 0.9863 of one horsepower. While HP and BHP are used to describe the total amount of power an engine can produce, PS is a more realistic measurement that considers the power left over after the gearbox, alternator, and water pump are working, as well as any loss of power due to friction. PS is the most commonly used measurement in Europe and is rarely used in everyday descriptions outside of the European Union.