Energy = the ability to do work! It takes energy to set cars in motion, to cool refrigerators, and to run factories. Anything that moves, plugs in, or creates heat or cold needs some kind of energy to make it work. (We are talking about human made things, not animals or plants; living things need different kinds of energy.) A graphic showing examples types of energy. Shown are (lightbulb), heat (toaster), sound (amplifier), electrical (battery), chemical (burger) and motion (car) energy.
Image 2. There are many different forms of energy. Some are light, heat, sound, electricity, chemical, and the energy of motion. Graphic: Newsela staff

Why is it important that we understand where energy comes from? Making and using some sources of energy can hurt life on our planet. Making and using other types of energy does little or no harm. It's important to know the difference.

Some sources of energy will eventually run out. (These are nonrenewable.) Others will never be used up. (These are renewable.) It's important to know which sources we will be able to use in the future.

Choose an event or phenomenon described in the text. Explain the causes and effects of your chosen topic, using details from the text.