SQL stands for Structured Query Language. It’s a standard language for accessing and manipulating databases. MySQL is a database management system, like SQL Server, Oracle, Informix, Postgres, etc. MySQL is an RDMS (Relational Database Management System).
When considering a utility for data management the two most popular choices are MySQL and SQL Server. Both are efficient at keeping your data organized and readily available through a user interface. Both technologies have the concept of the schema (that is table storage) for data storage.