Work is the scalar product of the force acting on an object and the displacement through which it acts. When work is done on or by a system, the energy of that system is always changed. If work is done slowly, we say that the power level is low. If work is done quickly, the power level is high. Kinetic energy is the energy an object has because of its motion, and potential energy is the energy an object has because of its location or configuration. If the energy of a system remains constant throughout a process, we say that energy is conserved.
W = F x d
Work is a measure of expended energy.