Car hydraulics are commonly found in low-rider cars. These cars have the ability to sit very low to the ground because their hydraulics, called "hydraulic lift kits" lower the car with the push of a button.
What Hydraulics Contain
Hydraulics are made from two pistons. Each piston is set into oil-filled glass cylinders. These to glass cylinders are connected at their bottoms by a pipe filled with oil.
Pushing down on one piston creates pressure on the oil around it and pushes the excess oil into the other glass cylinder, lifting the piston in it up.
One glass cylinder and piston may be bigger than the other cylinder and piston so that it will take less force to move the smaller piston. The bigger piston is called a master piston and the smaller is called a slave piston. Since the bigger piston creates more pressure and can move more, they often control several slave pistons that are all connected to it through a forked pipe full of oil.
The piston rising up and down raises the car up and down, making the car lower when needed.