Energy is the ability to do work. It gives us light and it makes things grow. It gives us heat and makes things move. Energy runs machines and makes technology work. It comes in many forms.
Mechanical energy puts things in motion.
Chemical energy is stored in food, wood, coal, petroleum and other fuels. Other forms of energy include electrical, radiant, heat and nuclear. When we use energy, we don't use it up. We transform it from one form into another. The availability and cost of energy are determining factors in the economic health and growth of societies.