4. Full virtualization
Another area where Linux (and Microsoft, for that matter) has made great progress recently has been in supporting virtualization. On a virtualized system, the real PC puts aside a box of memory in which another operating system can be installed and run. To this ‘child’ system, it looks like it is running on a real computer, but in reality all the inputs and outputs go through the parent system. There are advantages to this: a child system can be saved at any time as a file on the parent system, and restored into that state by reloading the file. Viruses and other threats can be blocked by the parent system too.
From a Linux perspective this means that a copy of Microsoft Windows can be installed on to a Linux system and run as if it were on a PC of its own. Although the Windows system doesn’t ‘see’ the Linux parent, files can be shared via a designated directory, usually located on the Desktop. Most Linux distros now come with a preferred virtualization system, and there are several others available – Vbox, QEMU, Xen and KVM are all well-known names in this area. Note that running a virtualized Windows system entails the same legal and financial obligations as running a ‘real’ one; the Windows software must be paid for and registered. You will also need a Windows CD to install it from.
Of course the same applies in reverse, and Linux operating systems can also be hosted on Windows PCs via virtualization. Microsoft has recently released their own free virtualization software, Virtual PC, which is proving very popular.
Tux on Paint on Windows on VBox on Ubuntu...