Star Trek is a science fiction television series created by Gene Roddenberry which aired from September 8, 1966 through September 2, 1969. 80 episodes were produced, 79 of which were aired. After the show was cancelled, it was placed in syndication, where it spawned a strong fan following and later achieved iconic status as a worldwide television phenomenon.

Set in the 23rd century, Star Trek follows the adventures of the starship Enterprise and its crew, led by Captain James T. Kirk (William Shatner), his First Officer Mr. Spock (Leonard Nimoy), and his Chief Medical Officer Leonard McCoy (DeForest Kelley).

William Shatner's voice-over introduction during each episode's opening credits stated the starship's purpose:

Space... the Final Frontier. These are the voyages of the starship Enterprise. Its five-year mission: to explore strange new worlds, to seek out new life and new civilizations, to boldly go where no man has gone before.

The success of the program was followed by five additional television series and ten theatrical movies with an 11th on the way for May 2009. The Guinness Book of Records lists it as having the largest number of spinoffs. Though the title of the original program was simply Star Trek, it has acquired the retronym Star Trek: The Original Series (sometimes shortened to ST:TOS or TOS), in order to distinguish this first series from the sequels which followed (all of which comprise the Star Trek universe or franchise).

When Star Trek debuted on NBC in 1966, it was not an immediate hit; ratings were low and advertising revenue was lackluster. Even prior to the end of the first season of Star Trek, there were already calls in the network for the cancellation of the series due to its low Nielsen ratings. During the show's second season, the threat of cancellation loomed. The show's devoted fanbase conducted an unprecedented letter-writing campaign, petitioning NBC to keep the show on the air. Its fans succeeded in gaining a third season; however, NBC subsequently moved the show to the Friday Night Death Slot at 10 PM. Gene Roddenberry resigned as line producer of Star Trek before the start of the final season to protest the changed timeslot, and was replaced by Fred Freiberger. NBC then substantially reduced Star Trek's budget which brought about a marked decline in the quality of many third season episodes. Nichelle Nichols observed that as a result of NBC's actions, "in the third season you saw fewer outdoor location shots, for example. Top writers, top guest stars, top anything you needed was harder to come by. Thus, Star Trek's demise became a self-fulfilling prophecy. And I can assure you, that is exactly as it was meant to be."

While Roddenberry remained nominally in charge of the series as executive producer, he essentially removed himself from the daily production of the show in its third season. Star Trek was cancelled at the end of its third season. However, it became extremely popular and gathered a large cult following in TV syndication during the 1970s.

Star Trek: The Animated Series, or The Animated Adventures of Gene Roddenberry's Star Trek, is an Emmy Award winning animated science fiction television series set in the Star Trek universe, and a continuation of Star Trek: The Original Series. The series was aired under the name Star Trek, but it has become widely known under this longer name (or abbreviated as ST:TAS or TAS) to differentiate it from the original live action Star Trek.

This animated series continues the adventures of the U.S.S. Enterprise, taking advantage of the visual freedom of animation to present stories with more alien elements. Written by Kenneth Chisholm

The adventures of the U.S.S. Enterprise, representing the United Federation of Planets on a five-year mission in outer space to explore new worlds, seek new life and new civilizations, and to boldly go where no man has gone before. The Enterprise is commanded by handsome and brash Captain James T. Kirk. His First Officer and best friend is Mr. Spock from the planet Vulcan, and Kirk's Medical Officer is Dr. McCoy. With its crew of approximately 430, the Enterprise battles aliens, megalomanical computers, time paradoxes, psychotic murderers, and even Genghis Khan! Written by Marty McKee

It is the 23rd century and together with the crew of the Federation starship Enterprise we travel across the galaxy to meet new and exciting life forms on distant planets. The 80 episode TV series which was produced from 1966 to 1969 has now cult character and has fans all over the world. Written by Harald Mayr