A Metal Halide lamp is a type of high-intensity discharge (HID) lamp that produces light by an electric arc through a gaseous mixture of vaporized mercury and metal halides. Metal halides are compounds of metals with bromine or iodine. Metal halide lamps have high luminous efficacy, colour rendition, and long lifespan. They are widely used for general lighting purposes both indoors and outdoors, such as commercial, industrial, and public spaces, parking lots, sports arenas, factories, and retail stores, as well as residential security lighting and automotive headlights.