The Harry Potter fandom is the community of fans of the Harry Potter books and films who participate in entertainment activities that revolve around the series, such as reading and writing fan fiction, creating and soliciting fan art, engaging in role-playing games, socialising on Harry Potter-based forums, and more. The fandom interacts online as well as offline through activities such as fan conventions, participating in cosplay, tours of iconic landmarks relevant to the books and production of the films, and parties held for the midnight release of each book and film.

Joanne Rowling ; born 31 July 1965), known by her pen name J. K. Rowling, is a British author and philanthropist. She wrote Harry Potter, a seven-volume fantasy series published from 1997 to 2007. The series has sold over 600 million copies, been translated into 84 languages, and spawned a global media franchise including films and video games. The Casual Vacancy (2012) was her first novel for adults. She writes Cormoran Strike, an ongoing crime fiction series, under the alias Robert Galbraith.