MySQL is a relational database that uses SQL (Structured Query Language) most popular language for adding, accessing and processing information in a database.
The base is open code (open source), can be downloaded from the Internet and used by each according to his needs, without the need for licensing. The advantage of MySQL is that specific information can be stored in separate, many small tables set between them establish connections (relations) rather than a single huge table.
This greatly facilitates and accelerates the processing of information.