In hydraulics-based systems, mechanical movement is produced by contained, pumped liquid, typically through hydraulic cylinders moving pistons. All types of hydraulic pumps pressurize liquids (typically hydraulic oils), moving a piston through a cylinder and control valves to control the fluid flow rate of oil. Hydraulics is a component of mechatronics, which combines mechanical, electronics and software engineering to design and manufacture products and processes. Force multiplication can be created by using a cylinder with a smaller diameter to push a larger piston in a larger cylinder. Often, there will be many pistons.