Joomla is an open source content management system (CMS) that is community-driven and maintained by volunteers. It has over 27,000 commits from hundreds of contributors and is used by over 7% of websites. Joomla is flexible, extensible, and easy to use. The speaker discussed Joomla's growth in usage and downloads over time as well as its large ecosystem of users, developers, and third party services. Challenges for Joomla include attracting and retaining contributors while continuing to provide an attractive solution.