The success of books and adaptations like The Lord of the Rings and Harry Potter, or a fantastic pirate epic like Pirates of the Caribbean and a video game world like World of Warcraft, shows that the fantasy genre enjoys immense popularity across the entire population. But what is fantasy, really? More importantly, what makes fantasy appealing? And what do we gain from dedicating ourselves to the often thousands of pages long works of the genre? This book, Fantasy: An Introduction, explores these questions for the first time from the perspectives of literature, communication theory, psychology, and philosophy. It reveals the history, structure, essence, and the variety of motives and insights of the works that transport their audience into imaginary worlds of adventure and magic, demonstrating that fantasy is much more than just good entertainment.