A bicycle is a vehicle. It has two wheels. The main part of the bicycle is the frame. You use the handlebars to steer the vehicle. The saddle is the seat where you sit. Your feet push the pedals. The pedals move a chain. The chain turns the back wheel, and the bicycle moves. Brakes are very important. They help you to stop the bicycle safely. Most bicycles also have a bell. You ring the bell to let people know you are there. A bicycle does not use gas. It is good for exercise.