An epistolary novel is a novel written as a series of letters between the fictional characters of a narrative. The term is often extended to cover novels that intersperse documents of other kinds with the letters, most commonly diary entries and newspaper clippings, and sometimes considered to include novels composed of documents even if they do not include letters at all. More recently, epistolaries may include electronic documents such as recordings and radio, blog posts, and e-mails. The word epistolary is derived from Latin from the Greek word epistolē, meaning a letter (see epistle). This type of fiction is also sometimes known by the German term Briefroman or more generally as epistolary fiction.

A novel is an extended work of narrative fiction usually written in prose and published as a book. The English word to describe such a work derives from the Italian: novella for "new", "news", or "short story ", itself from the Latin: novella, a singular noun use of the neuter plural of novellus, diminutive of novus, meaning "new". According to Margaret Doody, the novel has "a continuous and comprehensive history of about two thousand years", with its origins in the Ancient Greek and Roman novel, Medieval Chivalric romance, and in the tradition of the Italian Renaissance novella. The ancient romance form was revived by Romanticism, in the historical romances of Walter Scott and the Gothic novel. Some novelists, including Nathaniel Hawthorne, Herman Melville, Ann Radcliffe, and John Cowper Powys, preferred the term "romance". M. H. Abrams and Walter Scott have argued that a novel is a fiction narrative that displays a realistic depiction of the state of a society, while the romance encompasses any fictitious narrative that emphasizes marvellous or uncommon incidents. Works of fiction that include marvellous or uncommon incidents are also novels, including Mary Shelley's Frankenstein, J. R. R. Tolkien's The Lord of the Rings, and Harper Lee's To Kill a Mockingbird. Such "romances" should not be confused with the genre fiction romance novel, which focuses on romantic love.