WordPress is a free and open-source content management system written in PHP and paired with a MySQL or MariaDB database. Features include a plugin architecture and a template system, referred to within WordPress as Themes.

Elgg is open source social networking software that provides components for individuals and organizations to create an online social environment. It involves blogging, file sharing, networking, groups and other features

Drupal is a free and open-source web content management framework written in PHP and distributed under the GNU General Public License. Drupal provides a back-end framework for at least 2.3% of all websites worldwide – ranging from personal blogs to corporate, political, and government sites.

Ghost is a free and open source blogging platform written in JavaScript, it is designed to simplify the process of online publishing for both individual bloggers and online publications

Joomla is a free and open-source content management system for publishing web content, developed by Open Source Matters, Inc. It is built on a model–view–controller web application framework that can be used independently of the CMS.

OpenCart is a free online store management system. It is written in PHP, using a MySQL database. It has support for various languages and currencies

PrestaShop is a freemium open source e-commerce platform. It is written in the PHP with support for the MySQL database management system

OpenCMS is an open source content management system (CMS) based on Java and XML and it is used for public internet website, extranet or intranet

WooCommerce is an open-source e-commerce plugin for WordPress. It is designed mainly for small to large size online merchants using WordPress