Fire sprinklers can be automatic or open orifice. Automatic fire sprinklers use a fusible element that activates at a predetermined temperature. The fusible element either melts or has a frangible liquid-containing glass bulb that breaks, causing the water pressure in the fire sprinkler piping to push a plug out of the sprinkler orifice, resulting in water spraying from the orifice. The water stream strikes a deflector that forms the water into a spray pattern designed in support of the goals of the sprinkler type (i.e., control or suppression). Modern sprinkler heads are designed to direct spray downwards. Spray nozzles are available to provide spray in various directions and patterns. The majority of automatic fire sprinklers operate individually in a fire. Contrary to motion picture representation, the entire sprinkler system does not activate at the same time, unless the system is a special deluge type.