As of 2015, there are four types of .22 rimfire ammunition cartridges available for rifles and hand guns: .22 short, .22 long, .22 long rifle and .22 magnum. Rimfire is regarded as the first self-contained ammunition developed for hand guns and rifles, dating back to the mid-19th century.
The .22 short ammunition rounds are designed for small handguns and self defense. The .22 long and .22 long rifle rounds are designed for firing in rifles and provide users with better accuracy than using .22 short rounds, although any .22 cartridge works with a .22 caliber rifle. The .22 magnum round provides users with a larger projectile and more power.