The sixth of seven novels from British author J. K. Rowling's popular Harry Potter series. Set during Harry Potter's sixth year at Hogwarts, the novel explores Lord Voldemort's past, and Harry's preparations for the final battle amidst emerging romantic relationships and the emotional confusions and conflict resolutions characteristic of mid-adolescence. The book sold nine million copies in the first 24 hours after its release, a record at the time which was eventually broken by its sequel, Harry Potter and the Deathly Hallows. The 652 page book sold 65 million copies after its 2005 publication.