Hydraulic brakes and lifts operate based on Pascal's Law, which states that pressure applied to a confined, incompressible fluid is transmitted undiminished and equally in all directions.
Pascal's law (also Pascal's principle or the principle of transmission of fluid-pressure) is a principle in fluid mechanics given by Blaise Pascal that states that a pressure change at any point in a confined incompressible fluid is transmitted throughout the fluid such that the same change occurs everywhere. The law was established by French mathematician Blaise Pascal in 1653 and published in 1663.