In the books, the fantasy is about magic. Harry Potter is born with the power to do magic, as he is a wizard. He soon discovers that there are a lot of magic people, other wizard and witches, in the world, living unknown to most non-magical people (known as "muggles"). When he is eleven, he gets a letter inviting him to go to a boarding school called Hogwarts for young witches and wizards. Each book tells about one year of his life at school, about the people that he meets there, the things that he learns, and his adventures.
There are seven books total in the series. A series of movies about the first six books has been made by Warner Bros. They started making the movies in 2001. The sixth one, Harry Potter and the Half Blood Prince, was released on July 7, 2009. The first half of the final movie Harry Potter and the Deathly Hallows will be released in late November, 2010.