LED tube lights are replacements for fluorescent and CFL tubes. Some advantages to having LEDs in linear lighting fixtures are that LEDs have lower Wattage for the same level of lumens (light) cast, they last longer (up to 50,000 hours of use, equaling several years), and they contain no mercury or other harmful substances.
Some LED T8 tubes are compatible with ballasts existing in fluorescent fixtures, and some do not require ballasts, while others will work either way, with or without a ballast. Ballast compatibility and wiring diagrams are specified in the spec sheet for each LED tube, so you know exactly how each light works and can choose the right one for your application.
New to LED lighting terminology? Check out our Glossary of Terms