The AK-47 (also known as the Kalashnikov, AK, or in Russian slang, Kalash) is a selective-fire (semi-automatic and automatic), gas-operated assault rifle, developed in the Soviet Union (1946 - 1948) by Mikhail Kalashnikov. It is officially known in Soviet documentation as Avtomat Kalashnikova (Russian: Автомат Калашникова).

In 1946, the AK-47 was presented for official military trials. In 1948, the fixed-stock version was introduced into active service with selected units of the Soviet Army. An early development of the design was the AKS (S - Skladnoy or "folding"), which was equipped with an under folding metal shoulder stock. In 1949, the AK-47 was officially accepted by the Soviet Armed Forces and used by the majority of the member states of the Warsaw Pact.

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