An epic is a "[l]ong narrative poem in an elevated style that celebrates heroic achievement and treats themes of historical, national, religious, or legendary significance." Primary epics, also known as traditional or classical epics, were originally oral legends of a culture's heroes which have been recorded. Secondary epics, also known as literary epics, are works which began as literary forms and were "self-consciously produced by sophisticated poets who adapted aspects of traditional epic for specific literary and ideological purposes." Examples of primary epics include the Iliad and the Odyssey. Secondary epics include the Aeneid and John Milton's Paradise Lost ("Epic," par. 2), Paradise Regained, and Samson Agonistes.

The epic focuses on the acts of a "military, national, or religious" hero, who frequently has a divine parent ("Epic," par. 4), and who becomes the focal point for the narrative and whose life has broad cultural significance (Holman, "Epic" 161). The epic usually takes place in a broad geographical or cosmic setting and may include elements of the quest. Epics also often include references to the actions and participation of gods or mythological creatures ("Epic," par. 4). The style of writing has a majestic simplicity with elevated diction (Holman, "Epic" 161). The epic often begins in media res, that is, in the middle of the action (Holman, "Epic Formula" 162).

With the development and proliferation of the novel, the epic largely disappeared although the term epic is still used to refer to works which have a broad cultural, historical, or religious emphasis or which are cosmic in scope. Novels like J.R.R. Tolkien's Lord of the Rings, Frank Herbert's Dune series, or James Michener's Hawaii have been called epic as have movies like The Ten Commandments and Ben Hur.