Open source browser Firefox is expected to pass the billion mark in terms of downloads. 
Current figures indicates that Firefox dominates 1/3 of the browsers around the world! Windows explorer still remains the word leader with 60%, with Google Chrome, Safari and Opera all having less than a 5% share.
Mozilla Firefox was released in 2004 as an Open Source web browser, it is considered so popular because it is open source & cross platform, its easy to use interface, faster running times and extensive list of extensions and themes.
