Simulation rooms were chambers that provided hyperrealistic holographic simulations; such chambers were vast empty rooms, cold and sterile in nature, capable of holding several squads of trainees at a time. Simulation rooms felt and looked entirely real, capable of producing vibrations, flashes, terrain and cover, atmospheric conditions such as smoke, and all other manner of simulated effects needed for training. Simulation rooms could work in tandem with up to fifty other such rooms, the combined scenarios across multiple rooms simulating massive engagements with full air support, advancing armor, and even orbital bombardment.
Such rooms could be found aboard the Star Destroyers used by the First Order, and were commonly used to train First Order stormtroopers.