"The Wonderful Wizard of Oz (/ɒz/) is an American children's novel written by author L. Frank Baum and illustrated by W. W. Denslow, originally published by the George M. Hill Company in Chicago on May 17, 1900. It has since seen several reprints, most often under the title The Wizard of Oz, which is the title of the popular 1902 Broadway musical adaptation) as well as the iconic 1939 live-action film.

The story chronicles the adventures of a young farm girl named Dorothy in the magical Land of Oz, after she and her pet dog Toto are swept away from their Kansas home by a cyclone. (Baum uses the word cyclone while describing a tornado.) The book is one of the best-known stories in American literature and has been widely translated. The Library of Congress has declared it "America's greatest and best-loved homegrown fairytale." Its groundbreaking success and the success of the Broadway musical adapted from the novel led Baum to write thirteen additional Oz books that serve as official sequels to the first story.

Baum dedicated the book "to my good friend & comrade, My Wife," Maud Gage Baum. In January 1901, George M. Hill Company completed printing the first edition, a total of 10,000 copies, which quickly sold out. It sold three million copies by the time it entered the public domain in 1956."

Source: Wikipedia

Note that this tag covers the entire Oz canon created by Baum (and expanded upon by other writers, such as Ruth Plumly Thompson, after his death) that covers the Land of Oz and works that take place elsewhere on the fictional continent of Nonestica (also known as the Continent of Imagination) that the Land of Oz is part of. Any and all adaptations and derivative works (including those deemed "heretical" by fans and scholars) that take place in the Land of Oz are also covered, although some have tags of their own here, including the musical Wicked and the 2013 Disney film Oz the Great and Powerful.