Joomla is a popular new generation content management system, 'new' here refers to a CMS system that not only capable to serve as a flat article based library system, it is a system that offer ease of use, customizable and scalable, which means users are able to make use of the system to build different websites, add powerful plugins etc., these are not possible or perhaps difficult to be done with a conventional CMS.
Joomla is rather young player compare to others in the same industry. However, Joomla is already among the top few CMS that is getting lots of attention from the open source community, and 'yes' Joomla is released under GPL which is free to download and use.
This quick Joomla guide include a brief Joomla introduction, what you can do with Joomla and how to install Joomla in your cpanel hosting account, feel free to go through the web pages and grep a copy of latest stable Joomla and test it out yourself. If you have not yet signup a hosting account, you may want to consider our Joomla Hosting package.