A service pistol, also known as a personal weapon or an ordnance weapon, is any handgun issued to regular military personnel or law enforcement officers. Typically, service pistols are semi-automatic pistols issued to officers, non-commissioned officers, and rear-echelon support personnel for self-defence, though service pistols may also be issued to special forces as a backup for their primary weapons. Pistols are not typically issued to front-line infantry. Before firearms were commonplace, officers and non-commissioned officers typically carried swords.

A handgun is a firearm designed to be usable with only one hand. It is distinguished from a long gun which needs to be held by both hands and braced against the shoulder. Handguns have shorter effective ranges compared to long guns, and are much harder to shoot accurately. While most early handguns are single-shot pistols, the two most common types of handguns used in modern times are revolvers and semi-automatic pistols, although other handguns such as derringers and machine pistols also see infrequent usage.