One of the major responsibilities for the product owner is to develop and maintain the product backlog. The product backlog is a prioritized list of features needed to achieve the product vision. It is created by looking at the business plan, vision statement, proto type, etc of the product at hand. It becomes the centerpiece for discussion when discussing product direction during the sprint. The product backlog is composed of issues, features, functions, requirements, specifications and fixes, just to name a few. These entries make up the backlog and are also known as PBI’s or product backlog items. Each PBI is typically, but necessarily, created with a short description of the products functionality from the perspective of the user called user stories. The user stories are typically vague in solution but exact in the problem. The product owner is responsible for ordering PBI’s but the development team is responsible for estimating the completion. PBI’s in the backlog are estimates not commitments and PBI’s in the sprint are commitments but not guarantees. For this reason it is critical that the product backlog is consistently being updated to show the most recent status of the project.