Air compressors are mechanic devices that take in air and then compress and store it in a compressed form (meaning, it occupies less space than in its normal state). Air compressors are equipped with a tank that holds the compressed air inside. The tank is able to withstand all the pressure that the air applies inside it, but there are always signs that warn the user that damaging the tank can result in an accident.

One major difference between the various types of air compressors is that some of them are oil-lubricated while some others are not. Those that are not oil lubricated are also called oil-free compressors. Oil-free compressors boast the advantage that they dont need oil in order to operate, while oil-lubricated compressors do. Additionally, oil-lubricated compressors need to have their oil changed after certain periods of operation.

Another difference that can be seen among air compressors is that some of them are stationary (meaning they are static or unmovable), while some others are designed from scratch to be portable. Common air compressors are not used for industrial purposes, and they occupy the same volume as a medium-sized table. This type of compressor usually comes with built-in wheels in order to be more portable. However, air compressors aimed at industrial use can occupy areas larger than one, two, or even more rooms. These compressors are not intended to be moved more than a few times during their lifetime. Moving these compressors requires money as well as good planning.

Air compressors can be found in homes, small businesses, service stations, or in large industries. Their usage ranges from dust cleaning to heavy industry usage (inside machinery) and gas turbines. Air compressors play an essential role in the correct operation of many devices and procedures.