Compressed air cans, also known as gas dusters or canned air, are products used for cleaning or dusting electronic equipment and other sensitive devices. Despite the name "compressed air," these cans do not actually contain air (oxygen or nitrogen) but instead contain other gases that are compressible into liquids, such as hydrocarbon alkanes or hydrofluorocarbons. When sprayed, the liquid rapidly vaporizes into gas, creating a blast of gas to clean surfaces. True liquid air is impractical for storage in cans due to extreme pressure and temperature requirements. These products are widely used for dusting keyboards, cleaning computer vents, and other hard-to-reach areas. However, they must be used carefully since the gases can be harmful if inhaled and are sometimes flammable. The cans typically work best held upright and sprayed in short bursts to avoid the propellant liquid coming out and to maintain pressure. In summary, "compressed air cans" are actually cans of compressed gas propellants, not just air, designed to blow dust and dirt off sensitive equipment safely and effectively.