The document discusses plot structures in narratives. It describes Aristotle's original triangular structure of beginning, middle, and end. Gustav Freytag later expanded on this with his pyramid structure, adding elements of rising action, climax, and falling action. Tzvetan Todorov further developed Freytag's pyramid into a theory of equilibrium being disrupted and then restored by the story's resolution. Freytag's pyramid structure remains influential in Hollywood storytelling and film trailers.