"AK-47" roughly translates from Russian to English as "automatic Kalashnikov 47." Mikhail Kalashnikov is the inventor of the rifle, and 1947 is the year the final test model was produced.
During World War II, the German army fielded the first automatic assault rifle. Having faced these weapons, the Russian military pursued a similar design for its forces. A combat veteran, Kalashnikov realized the necessity of having a rugged and robust rifle. His design emphasized ease of use and combined it with broad environmental reliability. Since starting production in 1949, over 75 million AK-47s have been built as of 2014. It was extensively exported during the Cold War and has become one of the most widely used weapons in the world.