The Oz books form a book series that relates the fictional history of the Land of Oz. Oz was created by author L. Frank Baum, who wrote fourteen full-length Oz books. All of Baum's books are in the public domain in the United States. Even while he was alive, Baum was styled as "the Royal Historian of Oz" in order to emphasize the concept that Oz is an actual place on Earth, full of magic. In his Oz books, Baum created the illusion that characters relayed their adventures in Oz to Baum themselves, by means of a wireless telegraph.