James Watt, one of the key figures in the early development of steam engines, devised the concept of horsepower to make it easier for his customers to understand the amount of work his machines could perform.

• 瓦特，最早研制蒸汽机的关键人物之一，设计了马力这个概念，使他的用户能比较简单地理解他的机器能完成的工作量。