A lasgun was a continuous-wave laser projetor that was a great weapon in the Imperium. It was commonly a hand held pistol or rifle. Its firing pattern was typically a constant stream, but the nozzle could sometimes be adjusted to alter the width and spread of the beam. Its power source was a cell cartidge 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 the 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 Shield/ shields were being employed, lasguns were generally not used because contact of a lasgun beam with a sheild generally caused massive explosions that often killed everyone within a large radius. As a result, many soldiers preferred knives and swords in battle.
A larger version of the lasgun was a cannon, which had the same effects of a lasgun but on a larger scale. When the Baron Vladimir Harkonnen returned to Arrakis, he used these cannons to seal Atreides troops in caves.