8.1. Should you fear the GPL?

• The GPL stands for the "GNU General Public License", and is a commonly used open-source license.
• There are other open-source licenses that are similar to it.
• You may have heard about its "viral" nature, that forces code that uses GPLed code to be open-source as well. Should you worry about it?
• Usually there's nothing to be fear. The GPL (and all other free software licenses) explicitly allow making use (and even modifying) the software for internal use.
• Software that operates web-sites is considered software for internal use, as it is not distributed to the outside.

Amazon.com as an Example

• If we take Amazon.com for example, then they may make use of GPLed code for their web-site.
• If, however, they decide to distribute the code as a framework that allows setting up similar sites (say Amazonware), then they'll have to either comply by the terms of the GPL, and distribute it under a compatible free software license, or alternatively eliminate the use of the GPLed software.
• (Or if the option permits, get the copyright owner of the GPLed software to exempt them from the GPL somehow.)

Conclusion

• This presentation was directed primarily at people who manage or wish to set up web-sites.
• If you want to sell a framework that will facilitate setting up web-sites using LAMP, I wish you the best of luck, but you'll have to handle the legal problems involved in making use of open-source (and proprietary) software available on your own.
• Generally note that the distribution terms of proprietary software may give you even more trouble, as far as basing a web-site on them is concerned.