Joomla

Joomla is a PHP (programming language) and MySQL (database) based CMS (content management system), which allows structured maintenance of articles, menus and other standard and custom modules.

It is highly customisable, but yet easy to maintain. 

I think it is safe to assume that it is the second most powerful CMS for websites after typo3, which is much harder to maintain.

Or at least it was last time I checked.

Furthermore Joomla is Open Source, it exists for over 10 years and I am using it for my own website.

 

Here is a link.

https://www.joomla.org/

In case you want to display content in a multi column layout in your Joomla article, the below will line out how to do it.

Assumption is however that you are using the Joomla default template Protostar.