The brake shoe carries the brake lining, which is
riveted or glued to the shoe. When the brake is applied, the shoe moves and presses the
lining against the inside of the drum. The
friction between lining and drum provides the braking effort. Energy is dissipated as heat. Modern cars have
disc brakes all round, or discs at the front and drums at the rear. An advantage of discs is that they can dissipate heat more quickly than drums, reducing the risk of
overheating. Drums are retained at the rear because they are more effective than discs as a
parking brake. ==Railway tread brake==