Epos is the Greek noun from which we derive the term epic. Epos was the earliest form of verbal composition, existing long before the invention of writing. Epos generally refers to long narrative poems that bear the traditional memories of a culture and the performance of which are considered an important element of cultural identity. They are distinguished by generally having flat characters, agonistic plot, use of ring composition, and being built from formulae on the level of overall narrative, scene, and line. They are often accompanied by music. Major examples of epos include the Homeric epics, Gilgamesh, Beowulf, the Icelandic sagas, the Prince Marko epics of the guslari, and the songs of the African griots.