Alternate future

In science fiction stories involving time travel, an alternate future or alternative future is a possible future which never comes to pass, typically because someone travels back into the past and alters it so that the events of the alternate future cannot occur.

An alternate future differs from alternate history in that alternate history usually speculates on what might have happened in the past if some events in the past had occurred differently, while an alternative future usually speculates on what might happen in the future. Also, alternative histories commonly forgo time travel, while alternate futures do not.

An alternate future should not be confused with a possible future. Many science fiction stories are set in the future and treat it as if it were the only future within the context of the story; an "alternate" future story is specifically set in an "alternate" one, that is, one that, within the context of the story, does not come about to pass.

Examples of fictional works which show alternate futures include:
*"Back to the Future Part II"
*Mirror Universe (Star Trek)
*"A Sound of Thunder"
*In Marvel Comics:
**"Days of Future Past"
**Cable's future timeline dominated by Apocalypse and Stryfe
*"" ends up as an alternate future in the Marvel comics continuity
*"Danny Phantom"
*"Heroes"

ee also

*Parallel universe (fiction)
*Future history