Writing genres (more commonly known as literary genres) are categories that distinguish literature (including works of prose, poetry, drama, hybrid forms, etc.) based on some set of stylistic criteria. Sharing literary conventions, they typically consist of similarities in theme/topic, style, tropes, and storytelling devices; common settings and character types; and/or formulaic patterns of character interactions and events, and an overall predictable form.
A literary genre may fall under either one of two categories: (a) a work of fiction, involving non-factual descriptions and events invented by the author; or (b) a work of nonfiction, in which descriptions and events are understood to be factual. In literature, a work of fiction can refer to a flash narrative, short story, novella, and novel, the latter being the longest form of literary prose. Every work of fiction falls into a literary subgenre, each with its own style, tone, and storytelling devices.