Harry Potter is a series of seven fantasy novels written by British author J. K. Rowling. The books chronicle the adventures of the adolescent wizard Harry Potter, together with Ron Weasley and Hermione Granger, his friends from the Hogwarts School of Witchcraft and Wizardry. The central story arc concerns Harry's struggle against the evil wizard Lord Voldemort, who killed Harry's parents in his quest to conquer the wizarding world and subjugate non-magical (Muggle) people to his rule. Several successful derivative films, video games and other themed merchandise have been based upon the series.