Joomla is a free and open-source content management system (CMS) for publishing web content. It is built on a model–view–controller web application framework that can be used independently of the CMS.
Joomla is written in PHP, uses object-oriented programming (OOP) techniques (since version 1.5) and software design patterns, stores data in a MySQL, MS SQL (since version 2.5), or PostgreSQL (since version 3.0) database, and includes features such as page caching, RSS feeds, printable versions of pages, news flashes, blogs, polls, search, and support for language internationalization.
As of February 2014, Joomla has been downloaded over 50 million times. Over 7,700 free and commercial extensions are available from the official Joomla! Extension Directory, and more are available from other sources. It is estimated to be the second most used content management system on the Internet after WordPress.
Joomla 1.0 was released on September 22, 2005 as a rebranded release of Mambo 22.214.171.124 that combined other bug and moderate-level security fixes.
Joomla 1.5 was released on January 22, 2008, and the latest release of this version was 1.5.26 on March 27, 2012. This version was the first to attain long-term support (LTS); such versions are released each three major or minor releases and supported until three months after the next LTS version is released. April 2012 marks the official end-of-life of Joomla 1.5; with Joomla 3.0 released, support for Joomla 1.5 faded away in April 2013.
Joomla 1.6 was released on January 10, 2011. This version adds a full access control list functionality plus, user-defined category hierarchy, and admin interface improvements.
Joomla 1.7 was released on July 19, 2011, six months after 1.6.0. This version adds enhanced security and improved migration tools.
Joomla 2.5 was released on January 24, 2012, six months after 1.7.0. This version is a long term support (LTS) release. Originally this release was to be 1.8.0, however the developers announced August 9 that they would rename it to fit into a new version number scheme in which every LTS release is an X.5 release. This version was the first to run on other databases besides MySQL. Support for this version was extended until the end of 2014.
Joomla 3.0 was released on September 27, 2012. Originally, it was supposed to be released in July 2012; however, the January/July release schedule was uncomfortable for volunteers, and the schedule was changed to September/March releases. On December 24, 2012, it was decided to add one more version (3.2) to the 3.x series to improve the development life cycle and extend the support of LTS versions.
Joomla 3.1 was released on April 24, 2013. Release 3.1 includes several new features including tagging.
Joomla 3.2 was released on November 6, 2013. Release 3.2 highlighting Content Versioning.
Joomla 3.3 was released on April 30, 2014. Release 3.3 features improved password hashing and microdata and documentation powered by MediaWiki Translate extension.
On April 2014, Joomla Project Team announced that, it started following 'Semantic Versioning Scheme' for new Joomla builds. The earlier LTS (Long Term Support) and STS (Short Term Support) lifecycle policy is no longer observed. Joomla version 3.3.1 was the first version released under the new development strategy.
Joomla 3.4 was released on February 24, 2015. Release 3.4 contains improved security advancements, composer integration, Google new reCaptcha and several new features.
Like many other web applications, Joomla may be run on a LAMP stack.
Many web hosts have control panels for automatic installation of Joomla. On Windows, Joomla can be installed using the Microsoft Web Platform Installer, which automatically detects and installs dependencies, such as PHP or MySQL.
Many web sites provide information on installing and maintaining Joomla sites.
Joomla extensions extend the functionality of Joomla websites. Five types of extensions may be distinguished: components, modules, plugins, templates, and languages. Each of these extensions handles a specific function.
The quick start package contains selected templates and plugins with the configurations and data that is used in the demo website. The sample data can also be personalized based on the template in the quick start package and is different from the default Joomla! 3.x (2.5.x) package.