Star Trek is an American science fiction media franchise created by Gene Roddenberry, which began with the eponymous 1960s television series and quickly became a worldwide pop-culture phenomenon. The franchise has expanded into various films, television series, video games, novels, and comic books. With an estimated $10.6 billion in revenue, it is one of the most recognizable and highest-grossing media franchises of all time. The franchise began with Star Trek: The Original Series, which debuted in the US on September 8, 1966 and aired for three seasons on NBC. It was first broadcast on September 6, 1966 on Canada's CTV network. It followed the voyages of the starship USS Enterprise, a space exploration vessel built by the United Federation of Planets in the 23rd century, on a mission "to explore strange new worlds, to seek out new life and new civilizations, to boldly go where no man has gone before".