A compressor is a mechanical device that increases the pressure of
a gas by reducing its volume. An air compressor is a specific type
of gas compressor.
Compressors are similar to pumps: both increase the pressure on a
fluid and both can transport the fluid through a pipe. As gases are
compressible, the compressor also reduces the volume of a gas.
Liquids are relatively incompressible; while some can be
compressed, the main action of a pump is to pressurize and
transport liquids.
