Firefox runs on various versions of GNU/Linux, Mac OS X, Microsoft Windows and many other Unix-like operating systems. Its current stable release is version 3.6.10, released on September 15, 2010. Firefox’s source code is free software, released under a tri-license GNU GPL/GNU LGPL/MPL. Mozilla Firefox is a free and open source web browser descended from the Mozilla Application Suite and managed by Mozilla Corporation. As of August 2010, Firefox was the second most widely used browser, with 22.93% of worldwide usage share of web browsers, according to Net Applications. Other sources put Firefox’s usage share between 20% and 32%.To display web pages, Firefox uses the Gecko layout engine, which implements most current web standards in addition to several features which are intended to anticipate likely additions to the standards.
The latest Firefox features include tabbed browsing, spell checking, incremental find, live bookmarking, a download manager, private browsing, location-aware browsing (also known as “geolocation”) based exclusively on a Google service and an integrated search system that uses Google by default in most localizations. Functions can be added through extensions, created by third-party developers, of which there is a wide selection, a feature that has attracted many of Firefox’s users.