A fantasy story is one that includes witchcraft or magic and is usually set in an alternate reality. Fantasy stories often contain medieval elements, such as clothing, architecture, technology and language. Certain fantasy stories also include mythical creatures, such as dragons, chimeras, unicorns, sylphs and elementals.
As of 2014, some of the most popular fantasy series include "The Lord of the Rings," "The Chronicles of Narnia," "His Dark Materials" and "Harry Potter," which qualifies even though it's in a contemporary setting. Often, fantasy stories involve a quest that the main character and his band of companions must complete in order to save the world from an evil opposing force.
Fantasy stories can be based on folklore and traditions from different cultures all over the world. Fantasy stories often have intricate and complex magic systems. Writers are expected to include specific limits with their magic system in order to create a challenge for the characters who utilize it. If anything at all were possible, then the story would lack conflict.
Fantasy stories are sometimes confused with science fiction stories. The main difference between the two is that science fiction stories are usually more focused on advanced technology and set either in space or in a potential future.