Lamp (fixture)

A light fixture (US English), light fitting (UK English), or luminaire is an electrical device used to create artificial light by use of an electric lamp. All light fixtures have a fixture body and a light socket to hold the lamp and allow for its replacement. Fixtures may also have a switch to control the light, either attached to the lamp body or attached to the power cable. Permanent light fixtures, such as dining room chandeliers, may use a wall switch to turn them on and off; as such, these fixtures may have no switch on the fixture itself. Fixtures require an electrical connection to a power source, typically AC mains power, but also battery power for camping or emergency lights. Permanent lighting fixtures may be directly wired. Moveable lamps have a plug and cord so that they can be plugged into a wall socket. 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.

Portable light fixtures are often called "lamps", as in table lamp or desk lamp. In technical terminology, the lamp is the light source, which is typically called the light bulb. The term luminaire is recommended by the International Electrotechnical Commission (IEC) for technical use.

Fixture manufacturing began soon after production of the incandescent light bulb. When practical uses of fluorescent lighting were realized after 1924, the three leading companies to produce various fixtures were Lightolier, Artcraft Fluorescent Lighting Corporation, and Globe Lighting in the United States.

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