What characteristic distinguishes machine gun fire from other types of firearm operation?

Machine gun fire is primarily distinguished by its rate of fire, which is significantly higher than that of other firearm operations. Machine guns are designed to sustain continuous fire over a prolonged period, allowing them to deliver numerous rounds rapidly, which is essential for suppressing enemy positions, supporting infantry units, and providing a high volume of fire power during engagements. This capability is often measured in rounds per minute (RPM), and many machine guns can achieve rates of several hundred rounds per minute.

Unlike semi-automatic firearms, which fire a single round with each trigger pull, machine guns can fire continuously as long as the trigger is held down or until ammunition is exhausted. This sustained fire capability makes machine guns invaluable on the battlefield, particularly in offensive and defensive maneuvers. The other characteristics, such as type of ammunition, size of the weapon, and ergonomic design, may vary widely among firearms and do not uniquely identify machine guns in the same way that the rate of fire does.