SQL is a structured query language that is used to retrieve, create, add, remove, alter the data in a database. MySQL uses SQL for writing queries in altering and retrieving the data from the database.
SQL is used in different relational database systems like MySQL, MS SQL Server, Oracle. MySQL is a relational database management system that is built on SQL. SQL won't get updated and it is a fixed language. Since MySQL is a software, this will be newer versions coming. MySQL 8.0 GA is the latest version of MySQL.
You can go through this video on differences between SQL and MySQL for elaborated explanation: