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.

Moreover, these genres are formed by shared literary conventions that change over time as new genres emerge while others fade. Accordingly, they are often defined by the cultural expectations and needs of a particular historical and cultural moment or place.

According to Alastair Fowler, the following elements can define genres: organizational features (chapters, acts, scenes, stanzas); length; mood; style; the reader's role (e.g., in mystery works, readers are expected to interpret evidence); and the author's reason for writing (an epithalamion is a poem composed for marriage).

Genres are formed shared literary conventions that change over time as new genres emerge while others fade. As such, genres are not wholly fixed categories of writing; rather, their content evolves according to social and cultural contexts and contemporary questions of morals and norms.

The most enduring genres are those literary forms that were defined and performed by the Ancient Greeks; definitions sharpened by the proscriptions of modern civilization's earliest literary critics and rhetorical scholars, such as Plato, Aristotle, Socrates, Aeschylus, Aspasia, Euripides, and others. The prevailing genres of literary composition in Ancient Greece were all written and constructed to explore cultural, moral, or ethical questions; they were ultimately defined as the genres of epic, tragedy, and comedy. Aristotle's proscriptive analysis of tragedy, for example, as expressed in his Rhetoric and Poetics, saw it as having 6 parts (music, diction, plot, character, thought, and spectacle) working together in particular ways. Thus, Aristotle established one of the earliest delineations of the elements that define genre.

Action fiction and adventure fiction. The hero's journey is the most popular narrative structure of an adventure novel.

Comedy (including comic novel, light poetry, and comedic journalism): usually a fiction full of fun, fancy, and excitement, meant to entertain and sometimes cause intended laughter; but can be contained in all genres.