MonoCMS is a website content management system just like wordpress, blogger, the joomla etc. 
The difference between Monocms and the above is that it belongs to the category of non database systems without base data. Data is processed with PHP and stored in XML. 
So it uses the server's file system to store data, which makes it extremely simple, small in size and very fast.
MonoCMS is made by a Greek web developer who lives in Athens (Panagiotis or Pano z), so at the same time with English he acquired his Greek version.
The first syllable of the system name itself derives from the Greek word "only".
Today, as Panagiotis informed us (developer of the project) the new version 2.7 was released.
"Version 2.7 now also supports plugins. These extensions may be useful for users who want more features. Given that Monocms is a small system in volume, these extensions are likely to play a very important role in the overall system upgrade.
Using an extension is easy
- Download the extension
- Unzip the file.
– You upload it to the 'plugins' folder.
Settings related to a plugin are made within the file itself. ”
For more details, see changelog
