Battlestar Galactica began as a TV series, created by Glen A. Larson and airing on ABC. The show, greenlit to capitalize on the success of Star Wars, lasted only a single season, 1978-1779. The series soon returned as Galactica 1980, set decades later and focused on Earth. It too lasted only a single season.
In 2003, a reboot created by Ronald D. Moore debuted as a mini-series on the Sci-Fi channel. It was soon turned into an ongoing series, which lasted four seasons, garnering critical acclaim and running until 2009. A movie (not released theatrically) followed later that year. Caprica, a prequel series, debuted in 2010 but lasted only a single season.
At present, director Bryan Singer plans to reboot the series again, this time as a feature-film franchise, although this project has experienced delays and its fate is not yet known.