A Kalashnikov (Калашников) rifle is any one of a series of automatic rifles based on the original design of Mikhail Kalashnikov. They are officially known in Russian as "Avtomát Kaláshnikova" (Russian: Автома́т Кала́шникова, lit. 'Kalashnikov's Automatic Gun'), but are widely known as Kalashnikovs, AKs, or in Russian slang, a "Kalash". They were originally manufactured in the Soviet Union, primarily by Kalashnikov Concern, formerly Izhmash, but these rifles and their variants are now manufactured in many other countries. The Kalashnikov is one of the most widely used guns in the world, with an estimated 72 million rifles in global circulation.