What are the uses of "epic"?

As a literary term, "epic" modifies either "poem" or "hero." When we define a work of literature as an "epic poem," it will meet certain criteria. It is a long narrative poem: so it tells a story and has characters, a plot, and themes. The main character is referred to as the "epic hero"—he is larger-than-life, though not immortal. In one example of an epic poem, the title character of Beowulf is mortal but is extremely strong and is courageous as a leader and a fighter. He is able to tear off a limb from the great beast Grendel, which leads to the monster's death. He is also willing to sacrifice himself for the good of his men and for the good of Hrothgar's kingdom in fighting both Grendel and Grendel's mother.
An epic poem will depict the hero on his journey as he overcomes obstacles and fights for good. In an epic like Beowulf, good and evil are clearly defined. In other epics, like those by Homer, characterizations are sometimes more complex (take Odysseus in The Odyssey, for example). Epic poems reveal to the reader the values of the culture that produced them. For instance, the traits of the hero show us what characteristics were admirable in that culture.