The control panel that administrators use to manage the content, appearance and functionality of the site. Access to the back end is typically restricted to higher level users, such as publishers, administrators, and super users.

Stands for General public license. The most widespread such license is the GNU General Public License, GNU GPL or GPL for short. This software license is available in differrent versions and used by Joomla and many other FOSS projects. Joomla is licensed under GPL2 now.