In action only from September 1918, too late to matter in World War I, the BAR became the base of fire for the World War II American infantry squad, its single automatic rifleman providing sustained suppressive fire that riflemen with bolt-action or semi-automatic weapons could not match on their own.
Browning M1918 (BAR). Image cropped from Image:American WW II firearms.jpgjoelogon / Joe Loong, cropped and retouched by user:Atirador. · CC BY-SA 2.0 · sourceBrowning Automatic RifleUnknown authorUnknown author · Public domain · sourceJohn M. Browning, the inventor of the gun, and Mr. Burton, the Winchester expert on rifles, discussing the finer points of the Browning Light Gun (BAR) at the Winchester Plant.World War I U.S. Army Signal Corps Collection · Public domain · source