Before you can understand the Scrum process, it is important to first understand Scrum artifacts. Scrum artifacts are lists and schedules created in order to facilitate the completion of work during a Sprint.
Product Backlog - The product backlog is a prioritized to-do list. Anytime a task comes up during the duration of the project, the task is added to the product backlog and the list is re-prioritized. The only items on the product backlog that are detailed are the items that are of the highest priorities. This is done in order to ensure that extra and unnecessary work is not undertaken.
Release Burndown - The release burndown maps out in graphic form the relationship of the items on the product backlog to the time left in the Scrum project. During release planning, the initial release burndown chart is created; thereafter, it is updated as the product backlog changes.
Sprint Backlog - During the Sprint development session, the items that will appear on the sprint backlog for completion are determined. The sprint backlog does not change during the Sprint. Instead, team members complete the items on the backlog during the sprint duration - if additional items come up, then those items are placed on the product backlog for a future sprint. If the sprint becomes impossible to complete unless one of these new issues is completed, then the sprint is canceled and the team goes back to the sprint development meeting stage, generating a new sprint backlog in the process.
Sprint Burndown - The sprint burndown, like the release burndown, is a scheduled chart, but this chart demonstrates the relationship between items on the sprint backlog and the time left in the sprint. The sprint burndown demonstrates all the work left in the sprint.