A spud gun is a small toy gun used to fire a fragment of potato. To operate, one punctures the surface of a potato with the gun's hollow tip and pries out a small pellet which fits snugly in the muzzle. Squeezing the grip causes a small build-up of air pressure inside the toy which propels the projectile. The devices are usually short-range and low-powered.
The first spud gun was invented during the Great Depression, when few people would have wanted to waste a potato. The original inventor sold his patent to E. Joseph Cossman for US$600 after World War II. Cossman, the brother-in-law of "Uncle" Milton Levine, discovered there was a potato glut at the time, and through an advertising campaign sold two million spud guns in six months.