Some of the best-known books that have been frequently banned and challenged include the Harry Potter series by J.K. Rowling, "I Know Why the Caged Bird Sings" by Maya Angelou and "The Perks of Being a Wallflower" by Stephen Chbosky.
Books are banned and challenged for a variety of reasons, mainly when members of a community find a book's content, themes or messages inappropriate. Books exploring sexuality, especially in adolescents, and books that are perceived as being anti-Christian are some of the most frequently banned and challenged works, including Robie Harris' "It's Perfectly Normal" and Philip Pullman's "His Dark Materials" trilogy.
Historically, books were banned or censored for overt sexuality or for being critical of dominant political ideologies. James Joyce's "Ulysses," for example, was censored for its sexual content, while George Orwell's "Animal Farm" was banned in communist countries.
The American Library Association, which advocates for free expression and the rights of readers to access materials despite any perceived objectionable content, maintains a chronological list of frequently banned and challenged books. Some books frequently appear on lists of banned and challenged books, including "The Adventures of Huckleberry Finn" by Mark Twain and "The Catcher in the Rye" by J.D. Salinger.