What are the roles in a Scrum framework?

Scrum defines three roles. The Product Owner represents the customer and stakeholders, owns and prioritizes the product backlog, defines acceptance criteria, and makes decisions about what to build and in what order. The Scrum Master serves the team as a servant leader, removes impediments, coaches the team on Scrum practices, and protects the team from external interruptions. The Development Team is a self-organizing, cross-functional group of professionals who do the work of delivering increments. There is no project manager role in Scrum.