The Scrum Master is a role in Scrum – an Agile Framework for optimising the delivery of products. In most organisations, when someone is given this responsibility, they are concurrently given the authority necessary for success. Scrum Masters are in a different situation.
The Scrum Master is accountable for establishing Scrum as defined in the Scrum Guide. They do this by helping everyone understand Scrum theory and practice, both within the Scrum Team and the organisation.