Compressed air

Compressed air is air which is kept under a certain pressure, usually greater than that of the atmosphere.

Uses
Compressed air can be used in:
 * Pneumatics, the use of pressurized gases to do work. This includes compressed air vehicle propulsion and compressed air energy storage.
 * scuba diving, to inflate buoyancy devices. See also: Breathing gas
 * Compressed air can also be used for cooling using a vortex tube.
 * In gas dusters. It is then often called "Canned air".
 * In medical industries, compressed air is used to supply higher levels of Oxygen and other gasses to patients in need.