A frame story (also known as a frame tale or frame narrative) is a literary technique that sometimes serves as a companion piece to a story within a story, whereby an introductory or main narrative is presented, at least in part, for the purpose of setting the stage either for a more emphasized second narrative or for a set of shorter stories. The frame story leads readers from a first story into another, smaller one (or several ones) within it. The frame story may also be used to allow readers to understand a part of the story, then jump to another part that can now be understood. This is not however, to be mixed up with a narrative structure or character personality change.
The earliest known frame stories are those preserved on the ancient Egyptian Papyrus Westcar. Other early examples are from 1st millennium BC India, when the Sanskrit epics Mahabharata, Ramayana, Vishnu Sarma's Panchatantra, Jain Stories, Syntipas's The Seven Wise Masters, and the fable collections Hitopadesha and Vikram and The Vampire were written. This form gradually spread west through the centuries and became popular, giving rise to such classic frame tale collections as the One Thousand and One Nights (Arabian Nights), The Decameron, and Canterbury Tales. This format had flexibility in that various narrators could retain the stories they liked or understood, while dropping ones they didn't and adding new ones they heard from other places. This occurred particularly with One Thousand and One Nights, where different versions over the centuries have included different stories.