Product Backlog

An ordered list of everything that might be done to improve a product — features, bug fixes, technical improvements, and research spikes. The product owner owns and prioritizes the backlog. Items at the top are smaller, more detailed, and ready to be worked on; items lower down are larger and less defined. The backlog is never complete — it evolves as the team learns more about the product and user needs. A healthy backlog has enough refined items to fill two or three upcoming sprints without requiring significant planning work. The backlog is the single source of truth for what the team will work on next.