The hydraulic brakes used in automobiles is a direct application of :

Pascal's principle guarantees that the pressure is transmitted equally to all parts of the enclosed fluid system. This gives straight- line braking unless there is a fluid leak or something to cause a significant difference in the friction of the surfaces. The hydraulic brake is an arrangement of braking mechanism which uses brake fluid, typically containing ethylene glycol, to transfer pressure from the controlling unit, which is usually near the operator of the vehicle, to the actual brake mechanism, which is usually at or near the wheel of the vehicle.