Metafiction - Fiction in which the author self-consciously alludes to the artificiality or literariness of a work by parodying or departing from novelistic conventions and traditional narrative techniques

Intertextuality - The relationship between texts, especially literary ones

Mise-en-Abyme - Self-reflection within the structure of a literary work; a work employing self-reflection

The 4th Wall - The space which separates a performer or performances from an audience