Gas engine

A gas engine is like a very big bike that runs on gasoline instead of pedals. Inside the gas engine is a cylinder with pistons, spark plugs, and a gas tank. When you turn the key or push the start button, the spark plugs create sparks which ignite the gasoline in the cylinder. The force of the explosion pushes the pistons down, and this is what makes the engine go. The pistons then go up and down, over and over, which makes the car go forward.