This is a continuation of the Blog Herald’s Guide to the GPL License series. You can read part one and part two here.

One of the more common misconceptions about the GPL is that it is “viral” in nature and can “infect” any software that touches it.

While it is true that the GPL does have a viral component, it is only to ensure that derivative works based upon GPLed code are also released to the GPL. It is possible, and even common, for GPL applications and proprietary ones to co-exist side by side. For example, there are many proprietary programs, including Skype and MyDropBox, that run on Linux, which is GPLed.

However, when one delves into plugins and and themes, something of a gray area begins to emerge. Though a WordPress theme, for example, might not be based upon a GPL theme, it relies upon a GPL application to function. As such, it has been widely held that they are GPL-licensed, even if they haven’t been explicitly licensed as such. read more

This is a continuation of the Blog Herald’s Guide to the GPL License series. You can read the first part here.

It is easy to see why GPLed software would be of great interest to developers. GPL software, though not always free in terms of the money charged, always has to come with its source code and the ability to edit and customize the work.

This means that, if a developer obtains a GPLed application and needs to fix a bug or add a feature, they can do so. They are then free to distribute the fix under the same terms and, in doing so, are ensured that all future modifications are treated the same way. read more