There are several different kinds of pneumatic systems that exist, including:

Single-acting pneumatic systems: These systems use compressed air or gas to move a piston or cylinder in only one direction. The return movement is typically achieved by a spring or other external force.

Double-acting pneumatic systems: These systems use compressed air or gas to move a piston or cylinder in both directions, allowing for greater flexibility in controlling motion.

Rotary pneumatic systems: These systems use compressed air or gas to power rotary motion, typically through the use of a pneumatic motor or turbine.

Vacuum pneumatic systems: These systems use suction or negative pressure to move objects or materials, often through the use of a vacuum pump or suction cup.

Closed-loop pneumatic systems: These systems use a closed circuit of compressed air or gas to power motion, allowing for greater energy efficiency and control.

These different types of pneumatic systems can be combined with a variety of pneumatic components to create customized systems for specific applications in a wide range of industries.