PBI stands for Product Backlog Item, which is a single element of work that exists in the product backlog. PBIs can include user stories, epics, specifications, bugs, or change requirements. The Product Owner of an Agile team compiles and prioritizes the product backlog, putting the most urgent or important PBIs at the top. PBIs comprise tasks that need to be completed during a Scrum sprint—a PBI must be a small enough increment of work to be completed during a single sprint. PBIs are used in agile software development, especially in Scrum methodology. The key is understanding what a good PBI is and how to prioritize those items to increase efficiency and get the best possible results.