A Scrum Master works with the PRODUCT OWNER and the Scrum team to refine and improve processes where it makes sense. 

A Scrum Master has the following roles and responsibilities 

Coach team members 

The Scrum Master ensures that team members are well trained and have experience in Agile processes. The Scrum Master takes utmost care that the team members have a sense of project ownership and that teams are self-managed. 

Host daily stand-up meetings 

Daily Scrum, or stand-up, meetings last for 15 minutes. Each team member gets the opportunity to answer these questions: 

1. What did you do yesterday? 
2. What will you do today? 
3. Any issues and impediments 

Helps product owner with the product backlog 

The product owner is accountable for creating and maintaining the product backlog. The product backlog is a list of items that the agile team would work on to achieve the goals defined. The Scrum Master helps the product owner to refine the product backlog with the information gathered from daily stand-up meetings. 

Remove roadblocks 

The Scrum Master protects the team from distractions and roadblocks that can impede progress. 

For example, if team members are dragged into many unimportant meetings, the Scrum Master intervenes and determines who really needs to attend the meetings.  

Practices and principles 

To assure that work is not slowed down, the Scrum Master ACTS as a mentor and teacher to placidly onboard new EMPLOYEES or team members. The Scrum Master also helps new team members to understand the scope of a product and ensures that newly joined team members understand and adhere to Scrum practices and rules.