The Harmon Circle is a method for describing story structure, primarily derived from Joseph Campbell's monomyth. It was popularized by writer Dan Harmon, and explained in detail through the Channel 101 Wiki.
The basic narrative arc is divided into eight slices, each corresponding to a distinct plot point:
This principle can be applied to any medium or scenario, though it is most relevant to linear, time-based work. Any given piece can also have multiple interpretations, depending on which elements are given prominence.