Firefox version 1.0 was released on November 9, 2004. The browser was created by members of the Mozilla community as a lighter, standalone alternative to the bundled Mozilla Application Suite.
Firefox began in 2002 under the codename Phoenix and was later renamed Firebird before adopting the Firefox name. Its early appeal came from features such as tabbed browsing, an integrated pop-up blocker, and an extension system. At the time, it offered a popular open-source alternative to Microsoft’s dominant Internet Explorer 6.
The date is sometimes confused with later Firefox milestones: version 1.5 arrived in November 2005, version 2.0 in October 2006, and version 3.0 in June 2008. Firefox is also commonly confused with its engine: Firefox uses Gecko for page rendering and SpiderMonkey for JavaScript, but the browser itself—not either engine—is the answer to this question.