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Energy Around UsEnergy descriptions and measurements change a little when physicists start looking at the world. Geographers look at general ideas of energy circulating through systems. Physicists see things in very specific quantities, not always as systems. If you apply a force to an object, you put energy into the system. Energy must be used to do work or accelerate an object.You can also find energy in electricity, magnetism, kinetic energy, potential energy, springs, and different states of matter. Energy is not something you can hold or touch. Energy is a word to describe the power and effort of a force. As we said, energy can be found in many places. Active Energy vs. Stored Energy
Kinetic and potential energies are found in all objects. If an object is moving, it has a kinetic energy (KE). KE is an energy that can be applied to another object. Potential energy (PE) is used to describe objects that are not moving. The classic example of potential energy is to pick up a brick. When on the ground, the brick had no energy. When you picked it up, you applied work (the lifting action). That work was transformed into potential energy. Now the brick can do something It can fall. That fact may not be very impressive, but it's better than sitting in the dirt forever.
Season of SpringsThe study of springs is a whole section of physics. A spring that just sits there doesn't do much. When you push on it, you are storing large amounts of energy. It's not heating up or moving, but it now has strength. It can now expand and do work on a system. Anything that is elastic, such as a rubber band, uses the same kind of energy.
A rubber band can be stretched and then it is ready to do something. That stretching involves work and increases the potential energy. You can flatten a solid rubber ball and it will want to bounce back up. You can also pull the drawstring of a bow and the work will eventually make the arrow go flying. Those are all examples of your putting energy in and then something happening when the energy comes out.
Gases Storing EnergyGases? What can they do? Gases are great because they can be compressed. When the pressure increases, the amount of stored energy increases. It's like the springs, but different. Eventually that energy in the compressed gas can be let out to do something (work).In your car, there are shock absorbers. Some shocks have compressed gas in the cylinders. The energy in those cylinders keeps your car from bouncing too much in potholes. Think about wind. Wind is caused because of pressure differences in the atmosphere. When the wind blows it can do anything - turn windmills, help birds fly, make tornadoes, and all types of work. 
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