The MySQL database server is the most popular open source database around. The "SQL" part of MySQL stands for "structured query language," which is a standard interactive and programming language for getting information from and updating a database. This "language" allows you to make queries about the information in your database - data selection, insertion, updating, and locating. A database is a collection if information that is organized to allow for easy retrieval. You can have a database of customer addresses, a financial database, even a database about your DVD collection.
MySQL offers both a Community Edition (open source) and a Network Edition (licensed). MySQL Community Edition offers the advantages of being constantly updated and re-released to take advantage of the latest features. In addition, the MySQL open source version is completely free for those who are eligible for the general public license. However, if you are a private individual who plans to distribute the information in your database to others, you are required to use the MySQL Network Edition. For more specific information regarding the MySQL open source license, visit the MySQL website.
MySQL Network Edition is recommended for all business and government organizations, in order to avoid possible infringements of the open source license. In addition, MySQL Network Edition offers the advantage of having been more thoroughly tested for stability, reliability and security vulnerabilities.
If you need a database for private use, the MySQL Community Edition is a great place to start.