> What is the main difference between science fiction, and fantasy writing? Is there a distinction that seperates the two? I am wondering, because it just always seems to me that the two genres are grouped together. Anyone have any ideas?

Good thoughts have already been posted in response to your question; nonetheless, mine is that the distinction can't really be made in a great many cases -- hence, why they're usually grouped together in bookstores and also why this debate has never been resolved on Usenet, where newsgroups on the subject of these genres are grouped together into a single hierarchy. The division has been proposed several times, but it gets shot down, and perhaps rightfully so.

Some have suggested that the distinction is what might plausible happen vs. what can't happen. It's an interesting academic idea to think about, but how useful is it? Technically speaking, Star Wars is fantasy, not science fiction -- there's no science in it, it's got all the fantasy story archetypal characters, and the Force is not much more than a spiritualized magic scheme. But the *look* of Star Wars is nothing like what we think of as fantasy and everything of what we think of as science fiction. And except for the hard core science fiction fanatics that thrive on heavy scientific involvement in what they read, Star Wars' general appeal tends to leans more toward the science camp than fantasy. So even though Star Wars may technically be fantasy, how useful is that distinction?

Then there's my own novel, which has all the classic elements of fantasy -- wizards, dragons, magic, evil overlords, all in a medieval setting -- and yet there is some pseudo-scientific stuff that explains how "magic" works and the very universe is constructed. I don't think it crosses over into the science fiction camp, by any means, but it certainly breaks some of the conventions of fantasy.

Then you get into situations like Terry Brooks' "Running with the Demon," that has also been mentioned in this thread. It's kind of a three-way hybrid: science fiction-ish with its post-apocalyptic vision sequences; fantasy-ish with the way the invisible supernatural world behind every day reality is portrayed; but is perhaps more like a horror novel than either of the other two.

Another monkeywrench is Piers Anthony's Adept series, which takes place in two different worlds: one very clearly science fiction and the other very clearly fantasy.

The two genres go hand in hand so much, with such a huge percentage of the books that fall into either having cross-over elements, that I suspect it's not useful to distinguish between the two except in specific obvious cases.