Energy is measured in Joules, it used to be measured in calories but calories are only used to measure foodstuff. So when you eat food, you get more energy .Everyone has potential and Kinetic energy. In action it looks like this. Lets say a roller coaster is at the top of a big hill, and you start to go down. When the coaster is at the top of the hill, its storing is potential energy and when its going down, its converting to kinetic energy.
