Xen - Open Source Alternative to VMware

We will soon get to see virtualization of the linux environment, using XEN according to this art icle.

Virtualization, in simpler terms, would allow one to run Linux inside any other operating system like Windows as if it were another program. The running copy of linux, would however, not notice the difference. This is typically used for testing on more than one operating systems. Today VMware is the leader in this area.