Final answer:
A Gatling gun, invented by Richard Gatling, was a rapid-firing machine gun used in the Civil War and colonial warfare.
Step-by-step explanation:
A Gatling gun, invented by Richard Gatling and used in the Civil War, was a rapid-firing machine gun. It was a hand-cranked weapon that could fire several hundred rounds per minute. The use of Gatling guns by the British, French, and Americans gave them a significant advantage in colonial warfare during the late 19th and early 20th centuries.