MySQL is an open-source relational database management system that was developed in the 1990s. SQL, on the other hand, is a query language used to query relational databases. In other words, SQL is the programming language that database developers use to create, update, read, and delete the databases, tables, and records in a relational database management system while MySQL is an application used to keep data in the database structured and organized. SQL is the query language used to interact with MySQL and other relational database software like Oracle, SQL Server, or PostgreSQL. Each relational database management system uses a slight variation on the standard SQL language. Some queries that work with other database software might work with MySQL, and some may not.