Short answers, pulled from the story.
Fantasy is a genre of speculative fiction involving supernatural or magical elements, often including imaginary realms and creatures. It is distinguished from science fiction by not requiring scientific plausibility, and from horror by generally not centering on fear through protagonists' weaknesses. Authors use worldbuilding to create settings and characters that do not have to conform to the laws of history or nature.
George MacDonald, a Scottish author, is generally credited as the founder of modern fantasy literature. His 1858 novel Phantastes is widely considered the first fantasy novel written for adults. MacDonald was a major influence on both J. R. R. Tolkien and C. S. Lewis.
Weird Tales, published in 1923, was the first all-fantasy fiction magazine. The Magazine of Fantasy and Science Fiction followed, founded in 1949 when the pulp format was at the height of its popularity, and was instrumental in bringing fantasy fiction to wide audiences in the United States and the United Kingdom.
Fantasy elements appear in some of the oldest surviving literature, including the ancient Babylonian creation epic the Enuma Elish and the Epic of Gilgamesh. The Tales of the Court of King Khufu, preserved in the Westcar Papyrus and probably written in the second half of the eighteenth century BC, blends fantasy, historical fiction, and satire.
Dungeons and Dragons is the most successful and influential tabletop role-playing game. A 1999 survey in the United States found that of people aged 12 to 35 who played role-playing games regularly, two thirds played Dungeons and Dragons. Products branded Dungeons and Dragons accounted for over fifty percent of all role-playing game products sold in 2005.
Rosemary Jackson, in her 1981 book Fantasy: The Literature of Subversion, challenges Tzvetan Todorov's view of the fantastic as wish fulfillment in worlds superior to reality. Jackson argues that fantasy is inseparable from the social and cultural contexts in which it is produced, and that its unreal elements illuminate the limitations of the cultural order of their time. She also expands Todorov's structuralist approach to include psychoanalytical readings, drawing on Freud's theory of the unconscious.