If i could go back in time and tell my self different things about energy then i would tell my self first that there are three different types of energy. first you have the gravitational potention energy, elastic potencial energy and internal energy. i would tell my self that gravitational potential energy is when something or someone is at its highest point then the earthes gravity does work to bring it back down to the surface that it started from. Next i would tell my self that elastic potentioal energy is when you have a rubber band or a spring that does work on something to give it energy, and like flings it off. last is internal energy which is when something is doing work but after it is done doing work the temperature changes.