Manufactured near the end of WWI, the Browning Automatic Rifle, or BAR, was originally intended to be carried and fired much like the M1 Garand, that is, from the shoulder or from the hip, while delivering much more firepower. Unfortunately, due to the weight being twice as heavy as an M1 Garand, the BAR had to be fitted with a bipod, and by the time WWII rolled around it proved to be a capable light machine gun. The BAR was used for many years and, in the end, ceased to be used only because it could not be made to work adequately with new ammunition.
BAR (BAR M1918) on Wikipedia