Track lighting is a form of indoor lighting where the light fixtures are attached anywhere on a continuous "track" device which contains special electrical conductors to provide the power for the lighting. This is as opposed to the routing of traditional electrical wiring to individual light positions. These tracks can be mounted to ceilings or walls, lengthwise down beams, or crosswise across rafters or joists. They can also be hung with rods from especially high places like vaulted ceilings.

Typical systems have line voltage (100 volts in Japan, 120 in North America, 240 elsewhere) running through a recessed track. The track may have a second "hot" conductor, so that two circuits may control lighting on the same track. This is selected by placing the tab of the connector on the fixture to one side or the other when attaching it to the track. There are three standard types of tracks used in North America, as well as elsewhere in the world. They are often termed "H", "J", and "L" track, after the names of the manufacturers that established the standards, Halo, Juno, and Lightolier. To identify a track fixture, you may use the following two rules: 1. if it has three contacts, it is probably "H" type 2. If the contact-tips are 1 inch apart, it is probably "J" type, if they are 7/8 inch apart, it is probably "L" type.