Fantasy is a genre of art that uses magic and other supernatural forms as a primary element of plot, theme, or setting. The genre is generally distinguished from science fiction and horror by overall look, feel, and theme of the individual work, though there is a great deal of overlap between the three (collectively known as speculative fiction). In its broadest sense, fantasy covers works by many writers, artists, film makers, and musicians, from ancient myths and legends to many recent works embraced by a wide audience today.
Though the fantasy genre in its modern sense is less than two centuries old, its antecedents have a long and distinguished history. Elements of the supernatural and the fantastic were an element of literature from its beginning.
Even the most fantastic myths, legends and fairy tales, however, differ from modern fantasy genre in three respects:
Modern genre fantasy postulates a different reality, either a fantasy world separated from ours, or a hidden fantasy side of our own world. In addition, the rules, geography, history, etc. of this world tend to be defined, even if they are not described outright. Traditional fantastic tales take place in our world, often in the past or in far off, unknown places. It seldom describes the place or the time with any precision, often saying simply that it happened "long ago and far away." (A modern, rationalized analog to these stories can be found in the Lost World tales of the 19th and 20th centuries.)

The second difference is that the supernatural in fantasy is by design fictitious. In traditional tales the degree to which the author considered the supernatural to be real can span the spectrum from legends taken as reality to myths understood as describing in understandable terms more complicated reality, to late, wholly fictitious fairy tales.

Finally, the fantastic worlds of modern fantasy are created by an author or group of authors, often using traditional elements, but usually in a novel arrangement and with an individual interpretation. Traditional tales with fantasy elements used familiar myths and folklore, and any differences from tradition were considered variations on a theme; the traditional tales were never intended to be separate from the local supernatural folklore. Transitions between the traditional and modern modes of fantastic literature are evident in early Gothic novels, the ghost stories in vogue in the 19th century, and Romantic novels, all of which used extensively traditional fantastic motifs, but subjected them to authors' concepts.

By one standard, no work created before the fantasy genre was defined can be considered to belong to it, no matter how many fantastic elements it includes. By another, the genre includes the whole range of fantastic literature, both the modern genre and its traditional antecedents, as many elements which were treated as true (or at least not obviously untrue) by earlier authors are wholly fictitious and fantastic for modern readers. But even by the more limited definition a full examination of the history of the fantastic in literature is necessary to show the origins of the modern genre. Traditional works contain significant elements which modern fantasy authors have drawn upon extensively for inspiration in their own works.

The modern fantasy genre first took root during the 18th century with the increased popularity of fictional travelers' tales, influencing and being influenced by other early forms of speculative fiction along the way, finally unfurling in the 19th century from a literary tapestry of fantastic stories and gaining recognition as a distinct genre (mainly due to the nigh-ubiquitous recession of fantastic elements from "mainstream" fiction) in the late 1800's.

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