DBMS or Database Management Systems refer to software that is used to power a database. The simplest form is a single user database program such as Microsoft Access, but can expand out into MS SQL Server or MySQL. I plan to keep learning about the different options as far as DBMS software, but for now just MS SQL Server and MySQL caught my attention.
NOTE: SQL Server will always take as much memory as you allow regardless if it needs it or not. Keep this in mind when provisioning VM’s for SQL servers. Recommended 8 GB+
MySQL => Open sources DBMS.
MS SQL Server => Microsoft.