More about SCRUM:

Scrum is really a project management methodology to facilitate agile software development, and enable the creation of self-organizing agile teams. A ScrumMaster is like a traditional project manager in the sense that he/she oversees the centralization of team communication, requirements, schedules and progress.

But it is also very different because his/her main responsibility is to facilitate team communications and provide guidance and coaching, while removing impediments to the ability of the team to deliver its goals. Unlike a traditional project manager, the ScrumMaster doesn’t direct the team, because an agile team is based on the philosophy that a team member is committed to the other team members, not to a management authority.