The full form of AK47 is Avtomat Kalashnikova 1947. It’s used on Governmental ,Weapons & Forces in Worldwide

AK-47, also called Kalashnikov Model 1947, Soviet assault rifle, possibly the most widely used shoulder weapon in the world. The initials AK represent Avtomat Kalashnikova, Russian for “automatic Kalashnikov,” for its designer, Mikhail Timofeyevich Kalashnikov, who designed the accepted version of the weapon in 1947.

During World War II, the Sturmgewehr 44 rifle used by German forces made a deep impression on their Soviet counterparts. The select-fire rifle was chambered for a new intermediate cartridge, the 7.92×33mm Kurz, and combined the firepower of a submachine gun with the range and accuracy of a rifle. On 15 July 1943, an earlier model of the Sturmgewehr was demonstrated before the People’s Commissariat of Arms of the USSR. The Soviets were impressed with the weapon and immediately set about developing an intermediate caliber fully automatic rifle of their own,  to replace the PPSh-41 submachine guns and outdated Mosin–Nagant bolt-action rifles that armed most of the Soviet Army.

The Soviets soon developed the 7.62×39mm M43 cartridge, the semi-automatic SKS carbine and the RPD light machine gun. Shortly after World War II, the Soviets developed the AK-47 rifle, which would quickly replace the SKS in Soviet service. Introduced in 1959, the AKM is a lighter stamped steel version and the most ubiquitous variant of the entire AK series of firearms. In the 1960s, the Soviets introduced the RPK light machine gun, an AK type weapon with a stronger receiver, a longer heavy barrel, and a bipod, that would eventually replace the RPD light machine gun