Pistol

A Pistol, otherwise commonly known as a Handgun, is a "a firearm that is held and fired with one hand". There are several references to a "pistol" in the Halo universe:

United Nations Space Command

 * M6A Handgun
 * M6B Handgun
 * M6C Magnum Sidearm: a pistol featured in Halo 2 that is a cut-down version of the M6D Pistol
 * M6D Personal Defense Weapon System: a high powered pistol common in Halo: Combat Evolved.
 * M6G Personal Defense Weapon System: the M6-series pistol used in Halo 3

Covenant

 * Plasma Pistol: a common Covenant weapon that is standard armament for Grunts, Jackals, and Drones.
 * Mauler: A pistol-shotgun favored by Covenant Brute forces.