Firefox 12

The Mozilla Firefox project was created by Dave Hyatt and Blake Ross as an experimental branch of the Mozilla browser.

Firefox 1.0 was released on November 9, 2004, Firefox 1.5 was released on November 29, 2005, and version 2.0 was released on October 24, 2006. Firefox 3.0 was released on June 17, 2008, with version 3.5 and version 3.6 released on June 30, 2009 and January 21, 2010, respectively. Version 4.0 was released on March 22, 2011. Since the version 5.0, a rapid release cycle was put into effect, resulting in a new major version release every six weeks on Tuesday.

The latest version, Firefox 54.0, was released on June 13, 2017.

The project that became Firefox started as an experimental branch of the Mozilla Suite called m/b (or mozilla/browser). After it had been sufficiently developed, binaries for public testing appeared in September 2002 under the name Phoenix. This name carried the implication of the mythical firebird that rose triumphantly from the ashes of its dead predecessor, in this case from the "ashes" of Netscape Navigator after it had been killed off by Microsoft's Internet Explorer in the "First browser war". The history of the name Mozilla goes all the way back to the internal codename for the original 1994 Netscape Navigator browser, with the name meaning "Mosaic killer" and aiming to some similarity with the building-crushing Godzilla, as the company's goal was to displace NCSA Mosaic as the world's number one web browser. The name Mozilla was revived as the 1998 open sourcing spinoff organization from Netscape.

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