A firearm is any type of gun that uses an explosive charge and is designed to be readily carried and used by an individual. The term is legally defined further in different countries.
The Colt Single Action Army, a revolver chambered in .45 Colt
The Glock 19, a pistol chambered in 9×19mm Parabellum
The Mosin–Nagant, a rifle chambered in 7.62×54mmR
The M4 carbine, a carbine derivative of the M16 rifle, chambered in 5.56×45mm NATO
A gun is a device designed to propel a projectile using pressure or explosive force. The projectiles are typically solid, but can also be pressurized liquid, or gas. Solid projectiles may be free-flying or tethered. A large-caliber gun is also called a cannon.
SIG Pro semi-automatic pistol
Battleship USS Iowa fires a full broadside from its nine sixteen-inch naval guns
A 'flying-cloud thunderclap-eruptor,' a proto-gun firing thunderclap bombs, from the Huolongjing.
The first firearm (a "proto-gun"), the fire lance, from the Huolongjing.