Action

In physics, "action" is a concept used to describe the overall behavior of a system, calculated by integrating (adding up) the difference between kinetic energy (energy of motion) and potential energy (stored energy) over time. Think of it as a measure of the "effort" or "path" taken by an object or system to move from one state to another. According to the principle of least action, nature tends to follow the path that minimizes this quantity, guiding the natural motion of particles and objects.