The unit of measurement for energy is called the "joule." It is named after the English physicist James Prescott Joule, who made foundational contributions to the field of thermodynamics and the understanding of energy. One joule is defined as the amount of work done when a force of one newton displaces an object through a distance of one meter in the direction of the force. In terms of SI base units, one joule equals one kilogram meter squared per second squared (kg·m²/s²).