Final answer:
The Product Backlog is an ordered and dynamic list of user stories or functionalities that define what is needed to improve a product.
Step-by-step explanation:
The Product Backlog is an emergent, ordered list of what is needed to improve the product. It is a dynamic document that evolves with the product and is often managed using specialized software like JIRA or Trello. The items in the Product Backlog are typically in the form of user stories, which describe the functionality or desired outcome from the user's perspective.
For example, if a mobile app is being developed, some user stories in the Product Backlog might include 'As a user, I want to be able to create an account' or 'As a user, I want to be able to search for products in the app.'
As the product evolves and stakeholders provide feedback, new items can be added to the Product Backlog or existing items can be re-prioritized. The Product Owner is responsible for maintaining and managing the Product Backlog.