A Gatling gun is a rapid-fire, hand-cranked weapon that was popular during the late 19th century. It was invented by Richard Gatling in the early 1860s and was used extensively during the American Civil War. This type of gun has many synonyms, including machine gun, rapid-fire gun, automatic gun, and multi-barrel gun. The term "Gatling gun" is often used interchangeably with these synonyms, especially in modern times, where it is widely recognized as the quintessential rapid-fire weapon. Nevertheless, the term "Gatling gun" remains the most common term used to describe this type of weapon among gun enthusiasts and historians alike.