The M1919 Browning is a .30 caliber medium machine gun that was widely used during the 20th century. It was used as a light infantry, coaxial, mounted, aircraft, and anti-aircraft machine gun by the U.S. and many other countries, especially during World War II, the Korean War, and the Vietnam War. Although it began to be superseded by newer designs in the later half of the century (such as by the M60 machine gun), it remained in use in many North Atlantic Treaty Organization (NATO) countries and elsewhere for much longer. It is very similar in design to the larger .50 caliber (12.7 mm) M2 Machine Gun, which is also a Browning-designed weapon and is still in NATO service.
As a company or battalion support weapon, the M1919 required at least a two-man machine gun team. But in practice, four men were normally involved: the gunner (who fired the gun and when advancing carried the tripod and box of ammo), the assistant gunner (who helped feed the gun and carried the gun, and box of spare parts and tools), and two ammunition carriers. The original idea was to allow the gun to be more easily packed for transport, and featured a light barrel and bipod when first introduced as the M1919A1. Unfortunately, it quickly became clear that the gun was too heavy to be easily moved, while at the same time too light for sustained fire. This led to the M1919A2, which included a heavier barrel and tripod, and could be continuously fired for longer durations.