Avatar (2009 film) themselves to change into a Na'vi. "Avatar: A Confidential Report on the Biological and Social History of Pandora", a 224-page book in the form of a field guide to the film's fictional setting of the planet of Pandora, was released by Harper Entertainment on , 2009. It is presented as a compilation of data collected by the humans about Pandora and the life on it, written by Maria Wilhelm and Dirk Mathison. HarperFestival also released Wilhelm's 48-page "James Cameron's Avatar: The Reusable Scrapbook" for children. "The Art of Avatar" was released on , 2009, by Abrams Books. The book features
Avatar (2009 film) reached 2.7 million in the United States and Canada – overtaking "The Dark Knight" to become the best ever selling Blu-ray release in the region. The release later broke the Blu-ray sales record in the UK the following week. In its first three weeks of release, the film sold a total of DVD and Blu-ray discs combined, a new record for sales in that period. As of , 2012, DVD sales (not including Blu-ray) totaled over units sold with in revenue. "Avatar" retained its record as the top-selling Blu-ray in the US market until January 2015 when Disney's "Frozen" surpassed