Modern vehicles have brakes on all four wheels, operated by a hydraulic system, the brakes made be of a drum or disc type. The older vehicles generally have the drum system set up. Whereas the newer or high performance vehicles use disc brakes.

Disc brakes in general are more efficient. A disc brake is straddled by a brake caliper in which there are small hydraulic pistons worked by pressure from the master cylinder. Many cars have a power assistance to reduce the effort need to apply the brakes.

Usually the source of power is the pressure difference between the partial vacuum in the inlet and the outside air.