Literary genre identifies a class or kind of literature based on its form, theme, or style. Several characteristics differentiate each literary genre, and these characteristics are often used to categorize and arrange literary works. Writing has been classified by genre for centuries, but the phrase did not appear until the fourth century BCE in Aristotle's Poetics.

Despite the fact that there are several ways to describe a genre, it is customary to classify them based on the themes or topics they explore, such as romance, horror, mystery, or science fiction. They may also be classified according to the narrative genre or literary style, such as poetry, drama, or prose. It is also feasible to subcategorize a genre based on its particular characteristics or properties.

Understanding literary genre makes it easier for readers and authors to know the criteria and expectations of the many literary genres.

Readers of romance novels tend to be used to specific themes and cliches (not necessarily a bad word!), such as a central love story and a satisfying resolution. The same is true for writers of science fiction, who are required to follow genre-specific norms and requirements such as accurate scientific justifications and worldbuilding.

Historically, literary genres were used differently than they are now. In the past, genres were often employed to stifle authors' originality and enforce severe limitations; nowadays, however, they are seen as guidelines and starting points for creative expression. Although using genre tropes as a framework, several authors add their own distinctive twists and insights to their work.