Brake horsepower refers to the leftover energy after powering parts, such as the water pump, alternator and gearbox, while horsepower refers to the total engine output. HP is measured at the flywheel, while BHP is measured at the road wheel.
Car manufacturers frequently use BHP as a measure of engine power. PS, which means "horsepower" in German, is another favorite choice of car manufacturers for indicating engine power. One PS, which is also referred to as metric horsepower, is equivalent to 98.6 percent of BHP. Another less common unit used to measure engine power is the kilowatt. One kW is equivalent to 1.34 BHP.