In physics, a force is said to do work if, when acting, there is a displacement of the point of application in the direction of the force. For example, when a ball is held above the ground and then dropped, the work done on the ball as it falls is equal to the weight of the ball (a force) multiplied by the distance to the ground (a displacement).

Work transfers energy from one place to another, or one form to another.

According to Jammer the term work was introduced in 1826 by the French mathematician Gaspard-Gustave Coriolis as “weight lifted through a height”, which is based on the use of early steam engines to lift buckets of water out of flooded ore mines. According to Dugas, it is to Solomon of Caux “that we owe the term work in the sense that it is used in mechanics now”.