Epic is an ancient literary style. It is a large-scale long folk narrative poem describing legends or major historical events such as national origin, national migration, national war and immortal achievements of national heroes. It occupies an important position in the history of human culture. Epic has a simple and dignified narrative style, and its diachronic narrative essence and profound social significance enable it to fully reflect the social outlook and people's life in a historical period. Therefore, in this sense, every grand national epic is an encyclopedia to know a nation. On the other hand, a nation's epic often represents its outstanding achievements in literature and often becomes the source and model of its narrative literature. It is the crystallization of the collective wisdom of ancient people, embodies the national spirit of the nation, is a symbol of national culture and a monument to civilization.

For example, Homer's epic in ancient Greece is the oldest existing Greek literary work, representing the outstanding achievements of ancient Greek literature and the source and model of European narrative literature. Homer's epic is not only a narrative poem of human childhood full of fantasy and myth, but also reflects the social life and thoughts of ancient Greeks, and it is an encyclopedia of ancient Greek people's life. Engels once commented that Homer's epic is the main legacy of the Greeks "from barbarism to civilization". Thus, the cultural value of Homer's epic is self-evident.