Local legend has it that Oz, also known as The Emerald City, was inspired by a prominent castle-like building in the community of Castle Park near Holland, Michigan , where Baum lived during the summer. The yellow brick road was derived from a road at that time paved by yellow bricks. These bricks were located in Peekskill, New York, where Baum attended the Peekskill Military Academy. Baum scholars often refer to the 1893 Chicago World's Fair (the "White City") as an inspiration for the Emerald City. Other legends suggest that the inspiration came from the Hotel Del Coronado near San Diego, California. Baum was a frequent guest at the hotel and had written several of the Oz books there.  In a 1903 interview with Publishers Weekly ,  Baum said that the name "OZ" came from his file cabinet labeled "O–Z". 
Perhaps the biggest difference between the two is that in the novel Dorothy truly goes to the physical land of Oz whereas in the film it is merely a dream that is populated with people from her daily life who take the for of the Scarecrow, Tin Woodman, Lion, and Wicked Witch. There are large sections from the novel taken out of the film - the abyss, the china country, the Witch's minions, the Hammer-Heads - and, of course, several musical numbers and bits of exposition added in. The latter include the Wizard-as-fortuneteller and the Witch-as-neighbor, as well as the problems with Toto. Dorothy is a teenager in the movie and a child in the book. There are four witches in the novel but only three in the film. The Wicked Witch of the West also has a greater role in the film, as she is the dream version of Miss Gulch. The moral of the story is the same. The film's classic song "Somewhere Over The Rainbow" articulates Dorothy's desire to explore another world but by the end of both book and film, she learns "there is no place like home."