Last night Microsoft released the public beta, or test version, of Windows Vista. You can download it or order it on DVD from here. (http://www.microsoft.com/windowsvista/getready/preview.mspx)

Microsoft warns that the software should not be used "in a production environment or on a main machine in the home". The site also says that once the software is installed you will not be able to "roll-back" to the previous operating system - you must either install the final Vista release or re-install an older version of Windows.

Vista is available in English, German and Japanese and in 32-bit or 64-bit versions. The Vista Team blog is here. (http://blogs.technet.com/windowsvista/default.aspx)®

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