In arts that have a serial component exposition refers to the beginning of the work or first idea presented. It exposes the ideas upon which the work is based. In music is usually is a melodic theme (or set of themes). In stories it is the part that introduces the characters and the setting - the physical setting of where and when the story takes place, as well as the circumstances surrounding that story's beginning. Does the story begin with Cinderella living under the authority of her step-mother, or with her father before he remarries? The exposition introduces Cinderella, the step-mother, the two step-sisters, and a brief encounter with Prince Charming, although she doesn't know him as such yet. The setting is her father's house, and the circumstances is that she has become a slave now that her father is dead. Often an inciting incident will occur in the exposition. The expostition is also where the dramatic question is determined.