Backlog

An ever-evolving list of product requirements, prioritized by the customer (or customer representative), that conveys to an Agile team which features to implement first. Agile projects typically employ a top level backlog, known as a product backlog or release backlog, and each Agile team working on a project typically creates a backlog for each development iteration, known as an iteration backlog or sprint backlog.

At either the release level or iteration level, a backlog typically comprises features or requirements, often expressed in terms of user stories, that may be assigned estimates (e.g., in points or hours) by the development team. The customer or customer representative prioritizes the items in the backlog (and may assign them business value).