WordPress is an open source blog publishing application powered by PHP and MySQL which can also be used for basic content management. It has many features including a workflow^{[clarification needed]}, a plugin architecture, and an templating system. Used by over 2% of the 10,000 biggest websites, Wordpress is the most popular blog software in use today.^[1]

It was first released in May 2003 by Matt Mullenweg as a fork of b2/cafelog. As of September 2009, it is being used by 202 million websites worldwide.^[2][3]

WordPress has a templating system, which includes widgets that can be rearranged without editing PHP or HTML code, as well as themes that can be installed and switched between. The PHP and HTML code in themes can also be edited for more advanced customizations. WordPress also features integrated link management; a search engine-friendly, clean permalink structure; the ability to assign nested, multiple categories to articles; and support for tagging of posts and articles. Automatic filters that provide for proper formatting and styling of text in articles (for example, converting regular quotes to smart quotes) are also included. WordPress also supports the Trackback and Pingback standards for displaying links to other sites that have themselves linked to a post or article. Finally, WordPress has a rich plugin architecture which allows users and developers to extend its functionality beyond the features that come as part of the base install.

Native applications exist for Android^[4], iPhone/iPod Touch^[5], and BlackBerry^[6] which provide access to some of the features in the WordPress Admin panel and work with WordPress.com and many WordPress.org blogs.

WordPress first appeared in 2003 as a joint effort between Matt Mullenweg and Mike Little to create a fork of b2.^[10] The name WordPress was suggested by Christine Selleck, a friend of Mullenweg.^[11]