Definition:

A Backlog is a prioritized list of work items—such as features, enhancements, and bug fixes—that need to be completed for a product or project. It serves as a central source of tasks for the development team and is continuously updated as new requirements emerge.

Example:

In an Agile project, the Product Owner manages the Product Backlog, adding new user stories and reprioritizing existing items based on business value and customer feedback.