Disc and Drum Brake:- 

DISC BRAKE
Disc Brake

Mostly all the car have disc brake on the front wheels , and some have disc brake on all the four wheels. A disc brake uses a flat , round disc (or rotor), attached to the wheel hub instead of drum. The brake shoes ,also called pads, are positioned on opposite sides of the rotor and are mounted in the brake caliper. The calipers contains the hydraulic pistons used to apply the shoes and to the suspension members. Most brake disc are solid, but some vehicle have ventilated disc which contains radial vanes between it's rubbing surface for optimum cooling performance.
Drum Brakes
Drum Brakes

           The drum brakes is a traditional type of brake and is currently used in rear wheels of many vehicles. The shaped drum is attached to the axle or hub flange, just inside the wheel, and it rotates directly with wheel. The shoes are anchored to the backing plate so that they can pivot in and out of contact with the drum but cannot rotate with it. The anchors can be arranged in such a way that an opening of the shoe is placed over a round anchor or the smooth end ofo the shoe butts against a flat anchor block. The braking forces are transmitted from the shoe to the anchors , to the backing plate, and then to the suspension members .
          
           
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