If it's nighttime, street lamps are using electrical energy to make light. A car drives by your school or house. It is being powered by gasoline, a type of stored energy. Our bodies eat food, which has energy in it. We use that food to play or study.
Energy makes everything happen.
Energy can be divided into two different types, depending on whether the energy is moving or stored. An Online Exploration Explore the heart. Discover the complexities of its development and structure. Follow the blood through the blood vessels. Wander through the weblike body systems.