MySQL

MySQLis a relational database manager. Multithread and multiuser, it has more than six millions of installations worldwide. MySQL AB — since January 2008 is part of Sun Microsystems and this is in turn part of the Oracle Corporation since April 2009.

One of the licensing types is the GNU GPL for any use compatible with this licensing. But for those companies who want to incorporate it inside privatibe products, there is a specific type of licensing special for this purpose. It is developed mostly on ANSI C.

In contrast with projects like Apache, where software is developed by a public community and the copyright is owned by each developer. MySQL is propietary and is sponsored by a private company who owns most of the code. This is what makes the previous mentioned licensing scheme possible. In addition, the company offers support and services. For their operations, they hire people from around the world who collaborate via internet. MySQL AB was initially started by David Axmark, Allan Larsson and Michael Widenius.

Taken from Wikipedia, February 2010