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) make space for optimal picture and sound. The release also preserves the film's native 1.78:1 () format as Cameron felt that was the best format to watch the film. The Blu-ray disc contains DRM (BD+ 5) which some Blu-ray players might not support without a firmware update. "Avatar" set a first-day launch record in the U.S. for Blu-ray sales at 1.5 million units sold, breaking the record previously held by "The Dark Knight" (600,000 units sold). First-day DVD and Blu-ray sales combined were over four million units sold. In its first four days of release, sales of "Avatar" on Blu-ray