A disc brake is a type of brake that uses the calipers to squeeze pairs of pads against a disc or a rotor to create friction. There are two basic types of brake pad friction mechanisms: abrasive friction and adherent friction. This action slows the rotation of a shaft, such as a vehicle axle, either to reduce its rotational speed or to hold it stationary. The energy of motion is converted into heat, which must be dispersed.
Close-up of a disc brake on a Renault car
On automobiles, disc brakes are often located within the wheel
A drilled motorcycle brake disc
Front suspension and brake system on AMC Pacer with the rectangular open slots visible between the disc's friction surfaces
A brake is a mechanical device that inhibits motion by absorbing energy from a moving system. It is used for slowing or stopping a moving vehicle, wheel, axle, or to prevent its motion, most often accomplished by means of friction.
Disc brake on a motorcycle
Rendering of a drum brake
Single pivot side-pull bicycle caliper brake
Brake booster from a Geo Storm.