The literary genre of fantasy, along with science fiction and horror, can itself be put under the larger genre umbrella of speculative fiction. Thus, the definitions in this writeup should be considered roughly descriptive rather than prescriptive. There's a lot of genre crossover in some of my favorite speculative fiction (for instance, Brown Girl in the Ring, which has been alternately classified as SF, fantasy, or horror, depending on the eye of the beholding reviewer), and the best writers don't confine their work to little genre boxes.

However, in general, fantasy stories take place in a reality in which magic and/or supernatural or mythical beings exist. Elves, dragons, and unicorns are of course what many people think of when one mentions fantasy. However, the possibilites go much farther than this; look at any of the works of Neil Gaiman. Tim Powers' modern-day novels of ghosts and Las Vegas Tarot games are also fantasy, as is (in my opinion) Hopkinson's aforementioned tale of a young voodoo priestess in a futuristic Toronto.

But the genre distinction is about more than the trappings of myth or the fantastic. Part of it is about how the speculative fiction elements are handled.

Arthur C. Clarke once wrote, "Any science or technology which is sufficiently advanced is indistinguishable from magic." And some stories, most notably in space operas and science fantasies, do treat high technology as a type of "it's-just-there-and-it-works" magic; the focus of the tale is on the characters and their adventures, and science is never discussed. Conversely, some fantasies treat magic as an exacting technology; Michael Swanwick's science fiction often incorporates mythical elements, as does the work of some cyberpunk-era writers. So, the appearance of a god or a fairy in a story does not automatically make it fantasy; nor does staging an epic quest aboard space ships make for "true" science fiction.

Having said all that, fantasy literature has many sub-genres that characterize certain types of stories. The following are the classifications most widely recognized in the publishing industry.