If you are bored, read the GPL text at http://www.gnu.org/licenses/gpl-2.0.html. Licensing language on any topic can be a difficult thing to navigate and understand. Mostly, have just a basic understanding of the concept of GPL and let the lawyers, if necessary, sort out the rest.
A complete copy of the GPL is included in every copy of the WordPress download package in the license.txt file. The directory listing of the WordPress software files shown in Figure 2-2 lists the license.txt file.
Simply put, any iteration of a piece of software developed and released under the GPL must be released under the very same license in the future. Check out the nearby “The origins of WordPress” sidebar that tells the story of how the WordPress platform came to existence. Essentially, it was forked — meaning, the original software (in this case, a blogging platform called b2) was abandoned by its original developer, and the founders of WordPress took the b2 platform, called it WordPress, and began a new project with a new plan, outlook, and group of developers.
The origins of WordPress
Once upon a time, there was a simple PHP-based blogging platform called b2. This software, developed in 2001, ...