The 8.8 cm Flak 18/36/37/41 is a German 88 mm anti-aircraft and anti-tank artillery gun, developed in the 1930s. It was widely used by Germany throughout World War II and is one of the most recognized German weapons of that conflict. Development of the original model led to a wide variety of guns.
The name applies to a series of related guns, the first one officially called the 8.8 cm Flak 18, the improved 8.8 cm Flak 36, and later the 8.8 cm Flak 37. Flak is a contraction of German Flugabwehrkanone (also referred to as Fliegerabwehrkanone) meaning "aircraft-defense cannon", the original purpose of the weapon. In English, "flak" became a generic term for ground anti-aircraft fire. In informal use, the guns were universally known as the Acht-acht ("eight-eight") by Germans and the "eighty-eight" by the Allies.
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