Microsoft ships SQL Server with several built-in tools that database administrators (DBAs) can use to manage their SQL Server environment. With SQL Server 2005, Microsoft introduced SQL dynamic management views, or DMVs, as well as dynamic management functions, or DMFs. They provide plenty of information about server and database state, which you can use to monitor the health of a SQL Server instance, diagnose problems and tune SQL Server instance or database performance.
Checkout my article here, where you will find out how with detailed examples of some of the most common SQL DMVs (dynamic management views) and DMFs (dynamic managemnt functions) that can help you simplify administration of your SQL Server instances and databases.