Brake

Brake a device used to slow down or stop the movement of a body. Most vehicle brakes work on the principle of friction. They may operate by means of mechanical linkages, or by hydraulic or air pressure. car brakes operate hydraulically on all four wheels when the brake pedal is pressed. The hand, or parking brake works mechanically just on the rear wheels.

In the disc brake, breaking pressure forces pads against both sides of a disc that is attached to the wheel.
In the drum brake pedal pressure forces a brake shoe against a drum that is attached to the wheel.
The pads and shoes have a tough wear and heat resistant lining.