A lasgun was a continuous-wave laser projector that was perhaps the most widely used hand weapon in the Imperium. It commonly took the form of a pistol or rifle. Its firing pattern was typically a constant, narrow stream, but the nozzle could sometimes be adjusted to alter the width and spread of the beam. Its power source was a cell cartridge that could be replaced when depleted.
During the days of the Old Imperium, lasguns were often ornate in their design, with detailed scrollwork embedded into wooden handles. However, by the time of the Honored Matres, the designs had become less intricate and more functional.
Lasguns were the preferred weapon for armies. However, when shields were being employed, lasguns were generally not used because contact between a lasgun beam and a sheild generally caused massive explosions that often killed everyone within a large radius. As a result, many soldiers preferred knives and swords in combat, which in part helped maintain the art of swordsmanship, at least in the Old Imperium.