A flash is a evice used in photography that produces an instantaneous flash of artificial light (typically around 1/1000 to 1/200 of a second) at a color temperature of about 5500 K to help illuminate a scene. While flashes can be used for a variety of reasons (e.g., capturing quickly moving objects, creating a different temperature light than the ambient light) they are mostly used to illuminate scenes that do not have enough available light to adequately expose the photograph. The term flash can either refer to the flash of light itself, or as a colloquialism for the electronic flash unit which discharges the flash of light. The vast majority of flash units today are electronic, having evolved from single-use flash-bulbs and flammable powders.