Joomla is written in PHP and is distributed under the GNU GPL v2. There is a wide range of themes and modules for Joomla, which define the visual appearance or extend the Joomla core with additional functions.
The name Joomla is derived from "Jumla" in the Swahili language and has its roots in Arabic. Joomla is represented on the web with around 11 percent(CMS comparison).
Further reference:
https://de.wikipedia.org/wiki/Joomla
The following video provides an introduction to Joomla:
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