The gas most often used in lamps, particularly incandescent light bulbs, is argon. Argon is an inert gas, meaning it does not easily react with other substances. It is used inside lamps because it prevents the tungsten filament from oxidizing and deteriorating quickly. In addition, filling the bulb with argon reduces the evaporation of the tungsten filament, which helps to prolong the lamp's life and allows the filament to operate at higher temperatures for better efficiency. Other inert gases such as nitrogen, helium, neon, and krypton can also be used, but argon is the most common due to its balance of cost and effectiveness. This choice of inert gas helps to keep the lamp functioning longer without the filament burning out rapidly.