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Source Installing and configuring VirtualBox for virtual OSes

The world of virtual OSes continues to grow and grow. If you never experienced a virtual OS you should know they are outstanding tools that will help you with many tasks. You can test various environments, you can run software you couldn’t run before (i.e. games), you can run less stable OSes within more stable OSes. The limits almost seem boundless. And VirtualBox makes tackling virtual OSes not only easy, but free.
VirtualBox is easy to install – as easy as any other Linux application found within your distributions’ repositories. For this article we will be using Ubuntu Desktop 9.04. There will be no need to add any repository information.