Machine guns, also called automatic weapons, are firearms that can fire bullets continuously as long as their triggers are pressed. Synonyms for machine guns include submachine guns, assault rifles, automatic rifles, light machine guns, and heavy machine guns. Submachine guns are typically used for close-quarters combat, whereas assault rifles are commonly used by military forces due to their versatility in various combat scenarios. Automatic rifles, on the other hand, are mainly used for long-range engagements. Light machine guns are effective for providing suppressive fire, while heavy machine guns are mainly used for defensive purposes. These synonyms for machine guns have similar features and functions, but vary in size and specific use.