Pligg CMS is a free and open source Content Management System (CMS) written in PHP and using the popular open source MySQL database system for content storage. Pligg enables users to create an online community where anyone can submit articles, vote on them, and leave comments. Pligg CMS is incredibly easy to use and manage, and can easily help power social networks and other interactive communities. There are plenty of templates to choose from, along with a plethora of plugins and extensions. The software encourages visitors to register on your website so that they can submit their content and connect with other users. It is fairly easy to install Pligg CMS on an Ubuntu 14.04 VPS. The installation process should take about 5-10 minutes if you follow the very easy steps described below.