An epic can refer to two different things: an agile epic and a literary epic.

An agile epic is a large body of work that can be broken down into specific tasks called user stories based on the needs/requests of customers or end-users. Epics are an important practice for organizing work and creating a hierarchy. The idea is to break work down into shippable pieces so that large projects can actually get done and you can continue to ship value to your customers on a regular basis. Epics help teams break their work down while continuing to work towards a bigger goal.

On the other hand, a literary epic is a long narrative poem that tells a story, typically in third-person point of view. Epics often recount heroic deeds and can deal with various subjects such as myths, heroic legends, histories, edifying religious tales, animal stories, or philosophical or moral theories. Epic poetry has been and continues to be used by peoples all over the world to transmit their traditions from one generation to another, without the aid of writing. These traditions frequently consist of legendary narratives about the glorious deeds of their national heroes.

In general, an epic can be defined as a long narrative poem that tells a story, often recounting heroic deeds. It can also refer to a large body of work that can be broken down into specific tasks based on the needs/requests of customers or end-users.