Most modern cars have brakes on all four wheels.The brakes may be disc type or drum type.The front brakes play a greater part in stopping the car than the rear ones, because braking throws the car weight forward on to the front wheels.Many cars therefore have disc brakes which are generally more efficient, at the front and drum brakes at the rear.While All disc braking systems are used on some expensive or high-performance cars,and all-drum systems on some older or smaller cars.