"Science fiction" is a pretty broad spectrum that can include space travel, time travel, parallel universes, alien invasion (which might also fit under "horror"), just about anything set in the future or involving futuristic technology (though what counts as "futuristic" when a film is made may very well become reality not long afterwards, depending on just how futuristic it was to begin with), or... well, any number of other things.

See also DUST (web anthology), and science fiction: books, movies, TV shows, and webseries