Horsepower is a unit of measurement used to quantify the power output of engines and motors. It was originally developed in the late 18th century by the engineer James Watt to compare the power of steam engines to that of horses. One horsepower is equivalent to about 746 watts, which helps to understand how much work an engine can perform over time. In practical terms, horsepower indicates how quickly a vehicle can accelerate or how much weight it can pull. For example, a car with higher horsepower can generally achieve faster speeds and better performance than one with lower horsepower. This measurement is commonly used in the automotive industry to describe the capabilities of vehicles.