Firefox hit a significant milestone on Friday as it crossed (http://www.spreadfirefox.com/node/28337) the 400m download mark.

After its launch in 2004 the open source browser took around a year to reach 100m downloads in February 2005 before hitting the 200m milestone in July 2006. The number, of course, does not represent the actual number of Firefox users. Even disregarding failed downloads, many users have downloaded multiple copies of the open source browser.

Nonetheless 400m instances of people seeking to obtain the software is a significant achievement for the Mozilla Corporation.

Figures on the use of Firefox from different net metrics firms tend to differ. However, it is generally agreed that Firefox is obtaining a steadily increasing share of the browser market, which remains dominated by Microsoft's Internet Explorer web browser. Firefox represents 17.4 per cent of the browser market, up 5.6 percentage points from 11.8 per cent in September 2006, according to figures (http://www.itproductivity.org/browser.htm) from US consultancy firm Janco and the IT Productivity Center.

Over the last 12 months, Microsoft's Internet Explorer browser dropped 9.6 percentage points to a reach a market share of 63.9 per cent. As well as Firefox, Opera (up 1 percentage point) and Google Desktop (up 1.74 per cent) were also beneficiaries of the switch away from IE. ®

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