KNOPPIX is a bootable, live Linux system made by Klaus Knopper.
You can read more about it at http://knopper.net/knoppix/index-en.html .
Download it, burn it and it works like magic. Put it in any computer with a CD drive and you are good to go. It does not mater what or if an operating system is installed on that computer. The KNOPPIX CD is live, self contained and it will run even if the hard drive is damaged, hence I use it to fix broken computers.
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