A virtual dedicated server (VDS or VPS) can run a number of operating systems. To the operating system, the “virtual machine” appears as if it were real hardware. This means that you can install any operating system compatible with the x86 virtual machine that the virtualization manager provides. So you can have any flavour of Linux (CentOS, Ubuntu, etc) or you can even install Windows – typically this would be Server 2003 Web Edition or Standard. On top of this you can then install your favourite control panel system – for instance cPanel (http://cpanel.net), Plesk, or LXadmin (if you want a free one…)
It is recommended, however that if you choose Windows as an operating system on a server, you should assign the virtual machine at least 512MB of RAM so that it can operate efficiently without the machine using hard disk swap all the time. The increase in performance over a machine with less RAM is significant.
