The Ak-47 was named for it's inventor Mikhail Kalashnikov in 1945 but not put into production until 1947 in the Soviet Union, thus the number 47 in the model name. The actual designation comes from Automatic Kalashnikov Rifle, 1947 Model and has many slang terms including AK, Kalashnikov, and simply Kalash. The AK-47 was one of the first true assualt rifles and even today it's variants remain one of the most widely used and popular assualt rifles in the world because of it's durability, low cost, and ease of operation. It has been manufactured in many countries and has seen service with regular armed forces as well as irregular, revolutionary and terrorist organizations worldwide. More AK-type rifles have been produced than all other assault rifles combined.

The AK uses the standard 7.62x39mm cartridge and produces significant wounding (including hydrostatic shock) when the projectile tumbles and fragments in tissue; but it produces relatively minor wounds when the projectile exits the body before beginning to yaw.

The main advantages of the Kalashnikov rifle are its simple design, fairly compact size and adaptation to mass production. It is inexpensive to manufacture, and easy to clean and maintain. Its ruggedness and reliability are legendary. The AK-47 was initially designed for ease of operation and repair by glove-wearing Soviet soldiers in Arctic conditions. The large gas piston, generous clearances between moving parts, and tapered cartridge case design allow the gun to endure large amounts of foreign matter and fouling without failing to cycle. This reliability comes at the cost of accuracy, as the looser tolerances do not allow for precision and consistency. Reflecting Soviet infantry doctrine of its time, the rifle is meant to be part of massed infantry fire, not long range engagements. The average service life of an AK-47 is 20 to 40 years depending on the conditions to which it has been exposed.

The standard AK-47 or AKM fires the 7.62x39mm cartridge with a muzzle velocity of 710 metres per second (2,300 ft/s). Muzzle energy is 2,010 joules (1,480 ft·lbf). Projectile weight is normally 7.8 grams (120 gr). The AK-47 and AKM, with the 7.62×39mm cartridge, have a maximum effective range of around 400 metres (1,300 ft).