The MySQL database  is a relational database management system based on SQL (Structured Query Language) and was released in January of 1998.

MySQL runs on virtually all platforms, including Linux, Unix, and Windows. It is fully multi-threaded using kernel threads, and provides application program interfaces (APIs) for many programming languages, including C, C++, Eiffel, Java, Perl, PHP, Python, and Tcl.

MySQL is used in all sorts of applications, from data Web databases,warehousing, e-commerce,  logging applications and distributed applications. According to MySQL AB, their flagship product has over six million active MySQL installations worldwide. Customers include Cisco, Dun & Bradstreet, Google, NASA, Lufthansa, Hyperion, and Suzuki.

Zen Cart uses MySQL databases because it is a free, easy to use, open source program.