why they called the CMS with "joomla"?

CMS is not called Joomla.. Joomla is a CMS, but CMS is not joomla. CMS stands for Content Management Systems. There are lots of CMSs out there like Liferay, drupal, mambo, magnolia, etc. Joomla is just like one of them WraithStrider http://www.WraithStrider.com

The reason why joomla and other web content portals are called CMS, CMS stands for content management system, CMS, i have tried joomla it is a bit hard to use, there is an easy one called phpnuke a lot of professional people are using this CMS to create there site, you can download it from www.phpnuke.org for free. I have an site of my own www.cellphonejunky.co.uk it is builte from phpnuke, phpnuke is written in PHP programming, it is very easy to install and you get a lot of plug ins for phpnuke, i have tried joomla you don't get that much plug ins and themes for joomla but for phpnuke you get over 1000 blocks and modules and addons and mods they are called plugins you also get a lot of themes, and it is easy to use, joomla is a bit hard to use.