Mozilla Firefox is a free and open source[9] web browser descended from the Mozilla Application Suite and managed by Mozilla Corporation. As of March 2012, Firefox has approximately 25% of worldwide usage share of web browsers, making it the third most widely used browser, according to different estimates.[10][11][12] The browser has had particular success in Indonesia, Germany and Poland, where it is the most popular browser with 67%,[13] 50%[14] and 44%[15] of the market share respectively.

To display web pages, Firefox uses the Gecko layout engine, which implements most current web standards in addition to several features that are intended to anticipate likely additions to the standards.[16]

Firefox runs on various operating systems including Microsoft Windows, Linux, Mac OS X, and unofficially, FreeBSD as well as several other platforms. Its current stable release is version 12.0, released on April 24, 2012