Exposition (narrative)
（重定向自Infodump）
Narrative exposition, or simply exposition, is the insertion of important background information within a story; for example, information about the setting, characters' backstories, prior plot events, historical context, etc. In a specifically literary context, exposition appears in the form of expository writing embedded within the narrative. Exposition is one of four rhetorical modes (also known as modes of discourse), along with description, argumentation, and narration, as elucidated by Alexander Bain and John Genung. Each of the rhetorical modes is present in a variety of forms, and each has its own purpose and conventions. There are several ways to accomplish exposition.