What is the General Public License (GPL)?
There are now numerous Open Source Initiative approved OS licenses, but in the beginning there was just one, the General Public License. The intent of the drafters of the GPL, was to bring more and more software under the OS umbrella. This would be accomplished by the hereditary nature of the GPL. Those who obtain access to OS software under the GPL are required to re-license the software under the exact same terms as the GPL. Important requirements in the GPL are that the user must not charge for the further distribution of the underlying software and must also make the source code, including their additions, available to the downstream users. The General Public License, which is maintained by the Free Software Foundation, has gone through two modifications so that version 3.0 was released on June 29, 2007. However, because much software was released under the terms of the GPL, due to its hereditary nature, its terms remain profoundly influential.