Mozilla Firefox, or simply Firefox, is a free and open-source web browser developed by the Mozilla Foundation and its subsidiary, the Mozilla Corporation. Firefox uses the Gecko rendering engine to display web pages, which implements current and anticipated web standards. In 2017, Firefox began incorporating new technology under the code name Quantum to promote parallelism and a more intuitive user interface. Firefox is available for Windows 7 and later versions, macOS, and Linux. Its unofficial ports are available for various Unix and Unix-like operating systems, including FreeBSD, OpenBSD, NetBSD, illumos, and Solaris Unix. Firefox is also available for Android and iOS. However, the iOS version uses the WebKit layout engine instead of Gecko due to platform requirements, as with all other iOS web browsers. An optimized version of Firefox is also available on the Amazon Fire TV, as one of the two main browsers available with Amazon's Silk Browser.Firefox was created in 2002 under the code name "Phoenix" by the Mozilla community members who desired a standalone browser, rather than the Mozilla Application Suite bundle. During its beta phase, Firefox proved to be popular with its testers and was praised for its speed, security, and add-ons compared to Microsoft's then-dominant Internet Explorer 6. Firefox was released on November 9, 2004, and challenged Internet Explorer's dominance with 60 million downloads within nine months. Firefox is the spiritual successor of Netscape Navigator, as the Mozilla community was created by Netscape in 1998 before their acquisition by AOL.Firefox usage share grew to a peak of 32.21% in November 2009, with Firefox 3.5 overtaking Internet Explorer 7, although not all versions of Internet Explorer as a whole; its usage then declined in competition with Google Chrome. As of December 2021, according to StatCounter, Firefox has 8.34% usage share as a desktop web browser, making it the fourth-most popular desktop web browser after Google Chrome (66.35%), Safari (9.82%), and Microsoft Edge (9.53%), while its usage share across all platforms is lower at 3.91% in fourth place, after Google Chrome (64.06%), Safari (19.22%), and Edge (4.19%).