By Roger Parloff, senior editor @FortuneMagazineMay 6, 2013: 8:32 AM ET
(Fortune)
In 1999, Bill Gates famously wrote off Linux -- free, collaboratively written software -- as a threat to Windows only in the relatively tiny "student and hobbyist market." But by last year Microsoft itself had become one of the top 20 corporate contributors to Linux, writing code to make sure its products work well with the ubiquitous software -- a sign of just how thoroughly Linux has conquered the enterprise.
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