THE AK-47, OFFICIALLY KNOWN AS THE AVTOMAT KALASHNIKOVA (RUSSIAN: АВТОМАТ КАЛАШНИКОВА, LIT. 'KALASHNIKOV'S AUTOMATIC [RIFLE]'; ALSO KNOWN AS THE KALASHNIKOV OR JUST AK), IS A GAS-OPERATED ASSAULT RIFLE THAT IS CHAMBERED FOR THE 7.62×39MM CARTRIDGE. DEVELOPED IN THE SOVIET UNION BY RUSSIAN SMALL-ARMS DESIGNER MIKHAIL KALASHNIKOV, IT IS THE ORIGINATING FIREARM OF THE KALASHNIKOV (OR "AK") FAMILY OF RIFLES. AFTER MORE THAN SEVEN DECADES SINCE ITS CREATION, THE AK-47 MODEL AND ITS VARIANTS REMAIN ONE OF THE MOST POPULAR AND WIDELY USED FIREARMS IN THE WORLD.