What's sprint velocity?

Rate at which story points are achieved in sprints. Use sprint velocity to predict how many story points you can achieve in coming sprints.

For example, you observe that your product development team can complete on average 20 story points in a sprint. That makes the sprint velocity of your team 20. Assuming that the total backlog story points of your product is 200, you can predict that all product backlog items will be completed in 10 sprints.