Often when films are based on books, some details are shifted as the filmmakers take poetic license to create their own piece of art. "Coraline" is no exception to that rule. Based on the novel by Neil Gaiman, the film directed by Henry Selick takes certain liberties in characters, setting, props and order of events.
Not only were some characters introduced in the movie that weren't in the book, but also details about existing characters were portrayed differently in the film. For instance, Whybie (Whyborne is his full name) and his grandmother did not exist at all in the novel, but in the film Whybie serves as a confidant and friend to Coraline. He listens to her thoughts and worries, and the Other Whybie in the Other World performs a heroic sacrifice to help Coraline, yet this didn't occur in the novel. As for the existing characters in both the film and the novel, differences were largely minor. Coraline of the novel didn't have blue hair, and Other Mother of the novel didn't turn into a giant spider. Even the smaller character of Mr. Bobo (of the novel, Bobinsky in the film) is different in the film. In the novel he plays a much smaller role, never properly appearing until near the end, but in the film he's much more prominent and trains mice to play music.
The film had setting differences ranging from large scale to small. In the novel, Coraline was from England, but the film mentioned that she was from Michigan. The door that Coraline uses to travel from her world to the Other World was also arranged differently in the book. The film portrays the door as being small and hidden behind wallpaper, while in the novel the door was of a normal size and in perfect view in the parlor.
Some props used to move the plot along were used in varying ways in the film and novel, while others seemed to exist only in the film to enhance atmospheric effect. As for props appearing in both, the key to the Other World door was not sitting in a drawer in the novel as it did in the film. Rather, the key in the novel was on a ring of keys hanging from a door frame hook in the kitchen. Another difference in prop usage occurs at the climax of both the film and novel. In the novel and film, once Coraline escapes the Other World the severed hand of the Other Mother returns to try to get the key to the door back from Coraline. In the novel, Coraline sets up an imaginary tea party over the opening of a well by weighing down a picnic cloth with tea cups and placing the key in the center. When the hand goes for the key, its weight causes it to drop, with the key, into the well. In the film, Coraline attempts to drop the key down the well but is attacked by the hand. Whybie helps by smashing the hand with a rock, and they drop it and the key down the well.
Some events occur in different order or under difference circumstances in the novel and film, and most have to do with the buildup of the revelation that the Other World is not as pleasant as it first seems. For instance, in the novel Coraline learns by the end of her first visit to the Other World that her Other Parents want to sew buttons into her eyes, but in the film it takes three visits for the true nature of the Other Mother to be revealed. Also, the scene where Coraline goes shopping with her mother appears before Coraline ever visited the Other World in the novel, but in the movie it occurs after her second visit. Finally, the method for returning to her normal world differs in the film. In the novel, Coraline could only return to her own world through the door, but in the movie she returns if she falls asleep in the Other World.