In many ways, air conditioners are like refrigerators, but instead of securing the cold air inside, they blow the air around the room.
Air conditioners utilize refrigerant gas to cool down the warm air in a room and then blow the now-cooled air around the space with internal fans.
They must vent the hot air outside (usually via a window, ventilation shaft, or dedicated passage) with an exhaust hose. Ours come with a window kit which needs to be attached correctly. We can help you with instructions, should you need it.