An air cooler is any machine that is used to cool the air inside a vehicle, room, or building. An air cooler is used in casings which are thermally insulated to form refrigerators. The main use of an air cooler is to cool rooms and therefore, it is used in buildings, houses and other places.

There are several types of air coolers that are available for specific purposes:
* Absorption air cooler
* Dry air cooler
* Wet air cooler
* Ground coupled heat exchanger
* Deep water source cooling system
* Air and water coupled heat pumps


The coolers which are equipped with extra facilities such as dehumidifying and heating are called air conditioners.

A cooling fan is an electrically power driven machine that is used to generate airflow to provide ventilation, cooling, exhaust or some gaseous transfer and most importantly, comfort. A few characteristic applications of a cooling fan include comfort, climate control, ventilation, removing dust, and winnowing, cooling systems, drying, removing dust and providing a fire draft. A cooling fan is often used as an air freshener, by attaching sheets of fabric conditioner to the protective housing. This carries the fragrance and spreads it into the surrounding air.

An air conditioner is a machine, appliance, or system intended to remove heat from an area and reduce humidity, or supply heat to an area. A portable air conditioner is truly exceptional because it portable and can be moved from place to place without any difficulty. A portable air conditioner has an exhaust hose that needs to be vented out to some place but does not require any permanent installation, making it truly portable. A window venting kit is usually provided with a portable air conditioner. Nearly all portable air conditioners have castor wheels and thus, making it portable.