Forms of energy.
An object not in motion (such as a diver on a platform) may possess potential energy if it is capable of motion later.
The potential energy is converted to kinetic energy when the object is in motion (as when the diver jumps off the platform).
After the dive, the diver has less potential energy than before, and must expand more energy to get back on the platform.
Heat is released when energy is converted from one form to another.