A [[gun|firearm]] designed for sustained automatic fire. Machine guns are distinguished from [[assault rifle]]s and [[battle rifle]]s by size and ammunition capacity. Machine guns are divided into three categories:
* [b][[Light machine gun]]:[/b] Fires intermediate-power [[ammunition|cartridges]] (except earlier and [[World War II]] designs like the [[bren lmg|Bren]]). Light enough to be operated by one personnel. Are either belt-fed or [[magazine (weapon)|magazine]]-fed.
* [b]Medium and general-purpose machine gun:[/b] Fire full-power [[rifle cartridge]]s and serve in both infantry and emplaced roles. It typically require a crew to operate, due to their bulk.
* [b][[Heavy machine gun]]:[/b] Fires large-caliber cartridges (at least 12 mm but less than 20 mm), dedicated for anti-materiel role. Because of their weight and large size, HMGs are typically restricted to stationary positions.

h4. See also
* [[autocannon]]
* [[Gatling gun]]
* [[List of weapons]]
* [[minigun]]
マシンガン 機関銃 MG 机枪 機槍 汎用機関銃 GPMG