The Disc brake or disk rotor is a device for slowing or stopping the rotation of a wheel while it is in motion.A brake disc (or rotor in American English) is usually made of cast iron, but may in some cases be made of composites such as reinforced carbon�carbon or ceramic matrix composites. This is connected to the wheel and/or the axle. To stop the wheel, friction material in the form of brake pads (mounted on a device called a brake
caliper) is forced mechanically, hydraulically, pneumatically or electromagnetically against both sides of the disc. Friction causes the disc and Attached wheel to slow or stop. Brakes convert motion to heat, and if the brakes get too hot, they become less effective, a phenomenon known as brake fade.