1st March 2003, 9:02 PM
Fantasy pieces are usually set in the past or another world, while sci-fi is usually in the future and takes things that science has hinted at and goes crazy with it, such as time travel or light speed. A lot of fantasy also starts with "Once upon a time", or "a long time ago..." and is usually in a medieval-type LotR-ish setting, but that's not always neccessary. What matters is the type of story that it tells, which is usually that of a hero's journey or your basic good vs. evil storyline.