is an online, open source website creation tool written in PHP. But in non-geek speak, it's probably the easiest and most powerful blogging and website content management system (or CMS) in existence today.

is a free and open-source content management system (CMS) for publishing web content. It is built on a model–view–controller web application

Concrete5 was designed for ease of use, for users with a minimum of technical skills. It enables users to edit site content directly from the page.

eyeOS is a virtual web desktop that can uniquely serve any Windows and Linux application in a browser and integrate, at the same time, SaaS or local web services.

phpBB is free and open source forum software that is easy to use, powerful, and highly customisable. Our community offers extensive support to end users.

MyBB is a free and open source, community-based forum software project run by volunteers. And while MyBB is free for you, running the project is not.

OsTicket is a widely-used open source support ticket system. It seamlessly integrates inquiries created via email, phone and web-based forms into a simple easy-to-use multi-user web interface.

Magento is an open-source e-commerce platform written in PHP.

bbPress is forum software with a twist from the creators of WordPress. Easily setup discussion forums inside your WordPress.org powered site.