Harry Potter a cause-and-effect relationship, there is a clear correlation, and it seems that Harry Potter's cultural impact may be stronger than just a fandom bond. Many fan fiction and fan art works about "Harry Potter" have been made. In March 2007, "Harry Potter" was the most commonly searched fan fiction subject on the internet. At the University of Michigan in 2009, StarKid Productions performed an original musical parodying the "Harry Potter" series called "A Very Potter Musical". The musical was awarded "Entertainment Weekly"'s 10 Best Viral Videos of 2009. The sport Quidditch, played by characters in the "Harry Potter" series, was
The Magical Worlds of Harry Potter approval from Rowling, and has since received positive reviews from critics. An updated version of "The Magical Worlds of Harry Potter" was published in 2004 by Berkley Books. "The Magical Worlds of Harry Potter" explores the references to history, legends, and literature in J.K. Rowling's "Harry Potter" novels. David Colbert, the author of the book, told the "St. Louis Post-Dispatch" that the "Harry Potter" novels "are [...] literary treasure hunts for [Rowling's] readers. What seem like funny-sounding names and places and excursions into fantasy all have a basis in either history, myth or legend." He added, however, that he thinks