User stories provide the very foundation for a digital product. They come in various sizes. Large stories are called 'Epics', Medium stories are called 'Features', and Small stories are simply called 'User Stories'. Epics and features are typically containers to provide meaningful structure, while the User stories themselves are the actual functionality we want to build. Defining a user story map is often done together with a client, actual end users and key stakeholders. It must be based on research done on actual target users. User stories are organized into groups which provide a feature, and features belong to a certain Epic. A user story ideally has a very concrete and simple function "As who I can what so that why". In the example of a ticket system, a story can be "As a moviebuff I can read a review so that I can find out whether or not some people appreciated a movie".