The hydraulic "jack" used to lift cars in the garage is a hydraulic press, a tank with two pistons with a different cross section connected to it. It amplifies the force applied to the small piston. It gives a mechanical advantage.
The press doesn't just amplify the force, but it also changes the direction of application.

NB: The point of application of the forces should be situated over the cross section of the pistons. In this visual the red force is not applied correctly due to questions of design (to see its variation more clearly in the visual without making it excessively large).