|Initial release||May 27, 2003|
|Stable release||3.9.1 (May 8, 2014[±])|
WordPress is a free and open source blogging tool and a content management system (CMS) based on PHP and MySQL. Features include a plugin architecture and a template system. WordPress was used by more than 22.0% of the top 10 million websites as of August 2013[update]. WordPress is the most popular blogging system in use on the Web, at more than 60 million websites.
It was first released on May 27, 2003, by its founders, Matt Mullenweg and Mike Little, as a fork of b2/cafelog. The license under which WordPress software is released is the GPLv2 (or later) from the Free Software Foundation.
WordPress users may install and switch between themes. Themes allow users to change the look and functionality of a WordPress website or installation without altering the information content or structure of the site. Themes may be installed using the WordPress "Appearance" administration tool or theme folders may be uploaded via FTP. The PHP, HTML(hyper text markup language) and CSS(cascading style sheet ) code found in themes can be added or edited for providing advanced features. Thousands of WordPress themes exist, some free, and some paid for templates. WordPress users may also create and develop their own custom themes if they have the knowledge and skill to do so.
WordPress's plugin architecture allows users to extend its features. WordPress has a database of over 30,000 plugins, each of which offers custom functions and features enabling users to tailor their sites to their specific needs. These customizations range from search engine optimization, to client portals used to display private information to logged in users, to content displaying features, such as the addition of widgets and navigation bars.
Native applications exist for WebOS, Android, iOS (iPhone, iPod Touch, iPad), Windows Phone, and BlackBerry. These applications, designed by Automattic, allow a limited set of options, which include adding new blog posts and pages, commenting, moderating comments, replying to comments in addition to the ability to view the stats.
WordPress also features integrated link management; a search engine–friendly, clean permalink structure; the ability to assign multiple categories to articles; and support for tagging of posts and articles. Automatic filters are also included, providing standardized formatting and styling of text in articles (for example, converting regular quotes to smart quotes). WordPress also supports the Trackback and Pingback standards for displaying links to other sites that have themselves linked to a post or a article.
Prior to version 3, WordPress supported one blog per installation, although multiple concurrent copies may be run from different directories if configured to use separate database tables. WordPress Multi-User (WordPress MU, or WPMU) was a fork of WordPress created to allow multiple blogs to exist within one installation but is able to be administered by a centralized maintainer. WordPress MU makes it possible for those with websites to host their own blogging communities, as well as control and moderate all the blogs from a single dashboard. WordPress MU adds eight new data tables for each blog...
As of the release of WordPress 3, WordPress MU has merged with WordPress.
b2/cafelog, more commonly known as simply b2 or cafelog, was the precursor to WordPress. b2/cafelog was estimated to have been employed on approximately 2,000 blogs as of May 2003. It was written in PHP for use with MySQL by Michel Valdrighi, who is now a contributing developer to WordPress. Although WordPress is the official successor, another project, b2evolution, is also in active development.
WordPress first appeared in 2003 as a joint effort between Matt Mullenweg and Mike Little to create a fork of b2. Christine Selleck Tremoulet, a friend of Mullenweg, suggested the name WordPress.
In 2004 the licensing terms for the competing Movable Type package were changed by Six Apart and many of its most influential users migrated to WordPress. By October 2009 the 2009 Open Source content management system Market Share Report reached the conclusion that WordPress enjoyed the greatest brand strength of any open-source content-management systems.
In 2009, WordPress won the Packt best Open Source CMS Awards.
In 2010, WordPress won the Hall of Fame CMS category in the 2010 Open Source Awards.
|Legend:||Old version||Older version, still supported||Current version||Latest preview version||Future release|
|Version||Code name||Release date||Notes|
|Old version, no longer supported: 0.7||none||27 May 2003 ||Used the same file structure as its predecessor, b2/cafelog, and continued the numbering from its last release, 0.6. Only 0.71-gold is available for download in the official WordPress Release Archive page.|
|Old version, no longer supported: 1.0||Davis||3 January 2004 ||Added search engine friendly permalinks, multiple categories, dead simple installation and upgrade, comment moderation, XFN support, Atom support.|
|Old version, no longer supported: 1.2||Mingus||22 May 2004 ||Added support of Plugins; which same identification headers are used unchanged in WordPress releases as of 2011[update].|
|Old version, no longer supported: 1.5||Strayhorn||17 February 2005 ||Added a range of vital features, such as ability to manage static pages and a template/Theme system. It was also equipped with a new default template (code named Kubrick). designed by Michael Heilemann.|
|Old version, no longer supported: 2.0||Duke||31 December 2005 ||Added rich editing, better administration tools, image uploading, faster posting, improved import system, fully overhauled the back end, and various improvements to Plugin developers.|
|Old version, no longer supported: 2.1||Ella||22 January 2007 ||Corrected security issues, redesigned interface, enhanced editing tools (including integrated spell check and auto save), and improved content management options.|
|Old version, no longer supported: 2.2||Getz||16 May 2007 ||Added widget support for templates, updated Atom feed support, and speed optimizations.|
|Old version, no longer supported: 2.3||Dexter||24 September 2007 ||Added native tagging support, new taxonomy system for categories, and easy notification of updates, fully supports Atom 1.0, with the publishing protocol, and some much needed security fixes.|
|Old version, no longer supported: 2.5||Brecker||29 March 2008 ||Version 2.4 was skipped, so version 2.5 added two releases worth of new code. The administration interface was fully redesigned, and the WordPress website to match the new style.|
|Old version, no longer supported: 2.6||Tyner||15 July 2008 ||Added new features that made WordPress a more powerful CMS: it can now track changes to every post and page and allow easy posting from anywhere on the web.|
|Old version, no longer supported: 2.7||Coltrane||11 December 2008 ||Administration interface redesigned fully, added automatic upgrades and installing Plugins, from within the administration interface.|
|Old version, no longer supported: 2.8||Baker||10 June 2009 ||Had improvements in speed, added automatic installing of Themes from within administration interface, introduces the CodePress editor for syntax highlighting and a redesigned widget interface.|
|Old version, no longer supported: 2.9||Carmen||19 December 2009 ||Added global undo, built-in image editor, batch Plugin updating, and many less visible tweaks.|
|Old version, no longer supported: 3.0||Thelonious||17 June 2010 ||Added a new Theme application programming interfaces (API); the merge of WordPress and WordPress MU, creating the new multi-site functionality, a new default Theme called "Twenty Ten" and a refreshed, lighter admin UI.|
|Old version, no longer supported: 3.1||Reinhardt||23 February 2011 ||Added the Admin Bar, which is displayed on all blog pages when an admin is logged in, and Post Format, best explained as a Tumblr like micro-blogging feature. It provides easy access to many critical functions, such as comments and updates. Includes internal linking abilities, a newly streamlined writing interface, and many other changes.|
|Old version, no longer supported: 3.2||Gershwin||4 July 2011 ||Focused on making WordPress faster and lighter. Released only four months after version 3.1, reflecting the growing speed of development in the WordPress community.|
|Old version, no longer supported: 3.3||Sonny||12 December 2011 ||Focused on making WordPress friendlier for beginners and tablet computer users.|
|Old version, no longer supported: 3.4||Green||13 June 2012 ||Focused on improvements to Theme customization, Twitter integration and several minor changes.|
|Old version, no longer supported: 3.5||Elvin||11 December 2012 ||Support for the Retina Display, color picker, new Theme: Twenty Twelve, improved image workflow.|
|Old version, no longer supported: 3.6||Oscar||1 August 2013 ||New Theme: Twenty Thirteen ; Admin Enhancements - Post Formats UI Update, Menus UI improvements, Revisions Update, Autosave and Post Locking|
|Old version, no longer supported: 3.7||Basie||24 October 2013 ||Automatically apply maintenance and security updates in the background; Stronger password recommendations; Support for automatically installing the right language files and keeping them up to date|
|Old version, no longer supported: 3.8||Parker||12 December 2013 ||Improved admin interface; Responsive design for mobile devices; New typography using Open Sans; Admin color schemes; Redesigned Theme management interface; Simplified main dashboard; Twenty Fourteen magazine style default Theme; Second release using "Plugin-first development process"|
|Current stable version: 3.9||Smith||16 April 2014 ||"New features like live widget previews and the new Theme installer are now more ready for prime time, so check 'em out.
UI refinements when editing images and when working with media in the editor. We've also brought back some of the advanced display settings for images."
|Future release: 4.0||To be announced||27 August 2014 ||"To be announced."|
|Future release: 4.1||To be announced||10 December 2014 ||"To be announced."|
Many security issues have been uncovered in the software, particularly in 2007 and 2008. According to Secunia, WordPress in April 2009 had 7 unpatched security advisories (out of 32 total), with a maximum rating of "Less Critical." Secunia maintains an up-to-date list of WordPress vulnerabilities.
In January 2007, many high profile search engine optimization (SEO) blogs, as well as many low-profile commercial blogs featuring AdSense, were targeted and attacked with a WordPress exploit. A separate vulnerability on one of the project site's web servers allowed an attacker to introduce exploitable code in the form of a back door to some downloads of WordPress 2.1.1. The 2.1.2 release addressed this issue; an advisory released at the time advised all users to upgrade immediately.
In May 2007, a study revealed that 98% of WordPress blogs being run were exploitable because they were running outdated and unsupported versions of the software. In part to mitigate this problem, WordPress made updating the software a much easier, "one click" automated process in version 2.7 (released in December 2008). However, the filesystem security settings required to enable the update process can be an additional risk.
In a June 2007 interview, Stefan Esser, the founder of the PHP Security Response Team, spoke critically of WordPress's security track record, citing problems with the application's architecture that made it unnecessarily difficult to write code that is secure from SQL injection vulnerabilities, as well as some other problems.
In June 2013, it was found that some of the 50 most downloaded WordPress plugins were vulnerable to common Web attacks such as SQL injection and XSS. A separate inspection of the top-10 e-commerce plugins showed that 7 of them were vulnerable.
In an effort to promote better security, and to streamline the update experience overall, automatic background updates were introduced in WordPress 3.7.
Individual installations of WordPress can be protected with security plugins. Users can also protect their WordPress installations by taking steps such as keeping all WordPress installation, themes, and plugins updated, using only trusted themes and plugins, editing the site's .htaccess file to prevent many types of SQL injection attacks and block unauthorized access to sensitive files.
Independent analyst firm Real Story Group evaluates WordPress as a Web CMS.  In a 2014 analysis, the firm argued that growing enterprise demand for WordPress was part of a broader push for "embracing greater simplicity" in web publishing.
WordPress is also developed by its community, including WP testers, a group of volunteers who test each release. They have early access to nightly builds, beta versions and release candidates. Errors are documented in a special mailing list, or the project's Trac tool.
Though largely developed by the community surrounding it, WordPress is closely associated with Automattic, the company founded by Matt Mullenweg. On September 9, 2010, Automattic handed the WordPress trademark to the newly created WordPress Foundation, which is an umbrella organization supporting WordPress.org (including the software and archives for plugins and themes), bbPress and BuddyPress.
"WordCamp" is the name given to all WordPress-related gatherings, both informal unconferences and more formal conferences. The first such event was WordCamp 2006 in August 2006 in San Francisco, which lasted one day and had over 500 attendees. The first WordCamp outside San Francisco was held in Beijing in September 2007. Since then, there have been over 350 WordCamps in over 150 cities in 48 different countries around the world. WordCamp San Francisco, an annual event, remains the official annual conference of WordPress developers and users.
WordPress's primary support website is WordPress.org. This support website hosts both WordPress Codex, the online manual for WordPress and a living repository for WordPress information and documentation, and WordPress Forums, an active online community of WordPress users.
|Wikimedia Commons has media related to WordPress.|