Literature, in its broadest sense, is any written work; etymologically the term derives from Latin literatura/litteratura “writing formed with letters”, although some definitions include spoken or sung texts. More restrictively, it is writing that possesses literary merit, and language that foregrounds literariness, as opposed to ordinary language. Literature can be classified according to whether it is fiction or non-fiction and whether it is poetry or prose; it can be further distinguished according to major forms such as the novel, short story or drama; and works are often categorised according to historical periods or their adherence to certain aesthetic features or expectations (genre).

Taken to mean only written works, literature was first produced by some of the world’s earliest civilizations—those of Ancient Egypt and Sumeria—as early as the 4th millennium BC; taken to include spoken or sung texts, it originated even earlier, and some of the first written works may have been based on an already-existing oral tradition. As urban cultures and societies developed, there was a proliferation in the forms of literature. Developments in print technology allowed for literature to be distributed and experienced on an unprecedented scale, which has culminated in the twenty-first century in electronic literature.

A literary technique or literary device can be used by authors in order to enhance the written framework of a piece of literature, and produce specific effects. Literary techniques encompass a wide range of approaches to crafting a work: whether a work is narrated in first-person or from another perspective, whether to use a traditional linear narrative or a nonlinear narrative, or the choice of literary genre, are all examples of literary technique. They may indicate to a reader that there is a familiar structure and presentation to a work, such as a conventional murder-mystery novel; or, the author may choose to experiment with their technique to surprise the reader.

In this way, use of a technique can lead to the development of a new genre, as was the case with one of the first modern novels, Pamela by Samuel Richardson. Pamela is written as a collection of letter-writing correspondence, called “epistolary technique”; by using this technique, Pamela strengthened the tradition of the epistolary novel, a genre which had been practiced for some time already but without the same acclaim.

Literary technique is distinguished from literary device, as military strategy is distinguished from military tactics. Devices are specific constructions within the narrative that make it effective. Examples include metaphor, simile, ellipsis, narrative motifs, and allegory. Even simple word play functions as a literary device. The narrative mode may be considered a literary device, such as the use of stream-of-consciousness narrative.

Literary criticism implies a critique and evaluation of a piece of literature and, in some cases, it is used to improve a work in progress or a classical piece, as with an ongoing theatre production. Literary editors can serve a similar purpose for the authors with whom they work. There are many types of literary criticism and each can be used to critique a piece in a different way or critique a different aspect of a piece.