SCRUM, one of the "Agile Methodologies", is a well-defined set of guidelines that govern the development process of a product, from its design stages to its completion.

Product owner first creates list of user stories along with acceptance criteria. This is akin to requirement description stage in Waterfall model. In Agile, this list is known as product backlog. So PO, does UPDATE the proposed value of the stories that will help us in right prioritization.

1. During sprint planning team pulls the necessary user stories from the sprint backlog, do estimation, and decide on how much work NEEDS to be pulled.
2. The duration of the sprint is generally 2-3 weeks to complete its defined work for one sprint, but team meets daily (Daily Scrum) to assess its progress.
3. Along the way Scrum Master keeps them FOCUSED on a single goal.
4. At the END of the sprint, the work should be in potentially shippable-all quality metrics completed and ready to hand it over to the customer.
5. The sprint ends with a sprint review and retrospection.
6. After this, the next cycle or sprint begins and the cycle continues till all of the requirements of the product backlog completed.