MySQL is a relational database often used to store data for web sites working in conjunction with PHP. Relational means that different tables of the database can be cross referenced to one another. SQL stands for "Structured Query Language"
which is the standard language used to interact with databases. MySQL was built using the SQL base and released as an open source
database system. Because of its popularity, it is highly supported with PHP. Before you start learning to make databases it is important to understand more about what tables are.