A feature that is added to the backlog is commonly referred to as a story and has a specific suggested structure. The structure of a story is: "As a I want to so that " This is done so that the development team can identify the user, action and required result in a request and is a simple way of writing requests that anyone can understand. Example: As a wiki user I want a tools menu on the edit screen so that I can easily apply font formatting. A story is an independent, negotiable, valuable, estimable, small, testable requirement ("INVEST"). Despite being independent, i.e., they have no direct dependencies with other requirements, stories may be clustered into epics when represented on a product roadmap or further down in the backlog. [...] An epic is a group of related stories, mainly used in product roadmaps and the backlog for features that have not yet been analyzed enough to break down into component stories, which should be done before bringing it into a sprint so to reduce uncertainty. Epics can also be used at both program and project level.