Assault Riffle is selective-fire rifle that uses an intermediate cartridge and a detachable magazine, which usually short, compact, kind of selective-fire weapons that fire a cartridge intermediate in power between submachine gun and rifle cartridge. 

Assaul Rifle characteristics:

• capable to be adjusted to fire in semi-automatic, burst mode, and/or fully automatic mode in short term selective-fire.
• has an intermediate-power cartridge: more power than a pistol but less than a standard rifle or battle rifle, examples of intermediate cartridges are the 92×33mm Kurz, the 7.62x39mm, and 5.56×45mm NATO.
• ammunition must be supplied from a detachable box magazine.
• effective range of at least 300 metres (330 yards).

Assaul Rifle was first used in 1943.