How does science fiction differs from fantasy?

elements in science fiction could happen, and have changes of technology that we already have, and predict what we could havefantasy has things that would never happen, its more like a dream, usually...

Fantasy

Thematically, both often deal with the struggle of good over evil; Star wars is a great example of a story with both Sci-fi and fantasy characteristics (this combination is often called a 'space...

they are both usually telling about different world(s) although science fiction is more futuristic and sciency that deals with space and time whereas fantasy has a more magical touch to it.

There are many science fiction stories- the whole Atlantis genre, for example that have nothing to do with Space Travel but do go to Inner space- underwater, time travel, etc. Prepare to submerge!...