Understanding the GNU GPL or GNU General Public License is critical to understanding Open Source Software. But getting a good easy to understand explanation of this software license can be hard to come by. I’ll be the first to admit. I have tried explaining it to other people and found that I ended up confusing myself.

So who better to explain the GNU General Public License than founder of WordPress himself, Matt Mullenweg. Here’s the video:

A couple of notes I took along the way. First is I like how he summed up what the GPL license is. It’s like the “Bill of Rights” for software. He also explained the GPL as a fundamental set of laws of how open source software should be distributed.

The Redistributing of Software Licensed Under the GPL

So this is a critical element to the GPL that often goes unexplained. Thankfully Matt does such a good job explaining. Basically if you have a piece of software that you have built on top of software that is already licensed under the GPL, and you plan on redistributing that software, it too must be licensed under GPL.

This is why I think the GPL is by far the best open source license. It fully protects the “openness” behind the software. It should be noted how well WordPress has handled the issue of the GPL when it comes to not only it’s core, but also plugins and themes. They have done such a great job keeping the community as Open Source as possible.

The same cannot be said for other open source projects like Magento and SugarCRM. Although successful projects, they lack the ability to grow that WordPress has because they have not handled the “openness” issue with their contributions.

I hope this video and blog post helps give you a better understanding of the GNU General Public License. Once you truly understand it, it gets you excited to see all the posibilities and growth we can enjoy in the future in technology.