This is an interesting article. It was taken from Here

Microsoft's competitor Oracle has claimed that the software giant doesn't even use Windows servers to host their own web sites.
"Microsoft doesn't even use NT on their own Web site. They use Unix. It's rather ironic," said Oracle's senior vice president and chief marketing officer. Oracle has recently begun a marketing campaign promoting their own servers as "unbreakable."
Microsoft angrily denied Oracle's accusation as untrue, saying that they have only one website which don't use Windows 2000 and Windows.Net Server - the Hotmail free email service, which is being transitioned over to Microsoft software

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