An air compressor is a versatile piece of machinery designed to convert power from a motor or engine into pressurized air. Its use is widespread, often to aid professionals in activities like painting and nailing, or for everyday tasks such as inflating a tire or powering tools like a drill, sander, or saw.

When it comes to air compressors, there are two primary categories: positive displacement and negative displacement. The first type traps a certain volume of air and then reduces the size of the chamber, thus increasing the pressure. Examples include piston, diaphragm and rotary screw compressors. On the other hand, negative displacement compressors draw air in and then expelled it- a common example being the centrifugal compressor.

Compressors that use oil to cool the air as it is compressed are typically more cost-effective, but may require more maintenance. Alternatively, ‘oil-free’ compressors are a pricier option but entail reduced upkeep and are suitable for situations where the air is being used for breathing.

When it comes to choosing an air compressor, size is a critical factor. From portable mini-models to larger industrial varieties, the market has plenty of options. A larger unit can handle higher pressure and output greater volume of air.

An air compressor can range in price depending upon size, type, and amenities; however, they generally remain a cost-effective purchase. Additionally, air compressors are known for their minimal expenditure in upkeep and operation.