The lamps may be in sockets for easy replacement—or, in the case of some LED fixtures, hard-wired in place.
Light fixtures may also have other features, such as reflectors for directing the light, an aperture (with or without a lens), an outer shell or housing for lamp alignment and protection, an electrical ballast or power supply, and a shade to diffuse the light or direct it towards a workspace (e.g., a desk lamp).
A wide variety of special light fixtures are created for use in the automotive lighting industry, aerospace, marine and medicine sectors.
Both the International Electrotechnical Commission (IEC) and the Illuminating Engineering Society (IES) recommend the term luminaire for technical use.
[4] Fixture manufacturing began soon after production of the incandescent light bulb.