A literary genre is a category of literature. Genres may be determined by literary technique, tone, content, or length. They generally move from more abstract, encompassing classes, which are then further sub-divided into more concrete distinctions. The distinctions between genres and categories are flexible and loosely defined, and even the rules designating genres change over time and are fairly unstable.

Genre is any style or form of communication in any mode with socially agreed-upon conventions developed over time. In popular usage, it normally describes a category of literature, music, or other forms of art or entertainment, based on some set of stylistic criteria. Often, works fit into multiple genres by way of borrowing and recombining these conventions. Stand-alone texts, works, or pieces of communication may have individual styles, but genres are amalgams of these texts based on agreed-upon or socially inferred conventions. Some genres may have rigid, strictly adhered-to guidelines, while others may show great flexibility.