An epic is a large user story that cannot be delivered as defined within a single iteration or is large enough that it can be split into smaller user stories. Epics can help teams break their work down, while continuing to work towards a bigger goal. Epics usually cover a particular persona and give an overall idea of what is important to the user. An epic can be further broken down into various user stories that show individual tasks that a persona/user would like to perform. This can help the team organize their work and to create a hierarchy. This way, large projects can actually get completed and the team can continue to ship value to the customers on a regular basis.
There is no standard form to represent epics. Some teams use the familiar user story formats (As A, I want, So That or In Order To, As A, I want) while other teams represent the epics with a short phrase.
Paul the Painter, would like an easier way to manage his projects. This includes providing his client with accurate changes and the ability to bill them.
