You have the freedom to create and share network. GNU or GPL intended to guarantee your freedom the versions of programs, so that is will make sure that software if freely to use by others. The free software foundation’s using GNU or General Public Licence (GPL) mostly for the free software, but also for other internet works are applicable. Do you feel your web site is not promoting enough and not helping mush in selling? Perhaps the MySQL and PHP development system needed in your site presented by Joomla. This is like your IT consultant who helps you in designing and makes your website works more effective as the promotion.