Installing Ubuntu 13.10 on an external hard disk drive (HDD) connected to a computer that’s already running another operating system like Windows 7/8 or another Linux distribution is the subject of this article.
Installing Ubuntu or any other Linux distribution in standalone mode on an HDD is normally a simple, point-and-click operation. To do it on an external HDD connected to a computer running another operating system require a little bit more care, if you don’t want to overwrite the contents of the internal HDDs Master Boot Record (MBR). It’s still a simple process, but you have to watch out!
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