For use on questions regarding travel forwards or backwards (or both!) in time. This tag should be used in conjunction with the universe it is found in. Can also be used to signify that the question contains time travel when asking in relation to an identification question: [story-identification], [episode-identification], [character-identification] and [object-identification].

Time travel refers to the ability to move through time in a manner which does not respect the normal, sequential ordering of events. Depending on the circumstances surrounding this ability, one may be moving from one temporal event to another wilfully, randomly, or under the influence of an outside agent or being. Time travel is a frequent feature of science fiction. For example:

  • The protagonist of H.G. Wells' The Time Machine builds a machine that allows him to travel backwards or forwards in time at will to precise years
  • In Slaughterhouse Five (K. Vonnegut, 1969), army veteran and Dresden firebombing survivor Billy Pilgrim moves through time against his will after an alien abduction
  • In the Star Trek universe, starships can travel to the past by executing a "slingshot" maneuver around a star at maximum warp, subject to very delicate calculations (see, for instance, Star Trek IV: The Voyage Home)
  • Specifically in the TV series Star Trek: Voyager and Star Trek: Enterprise, the future of Starfleet is depicted as being heavily involved with time travel and the policing of timelines
  • Superman uses his ability to fly at great speed around the Earth to reverse time and change recent events in Superman (1978)
  • In Primer (2004), the protagonists build a device that allows them to repeatedly travel several hours back in time (with eventual dire consequences)

Use this tag for questions concerning time travel and its effects, as depicted in works of science fiction.