Having the ability to run different operating systems on a single machine can provide a whole host of different opportunities, especially if you don't to reboot or leave your current OS. Such a facility could be extremely useful if you wish to test a newer version of an existing operating system in order to see if it's compatible with your current hardware, or even to run an alternative OS, for a greater choice of software and other tools..

VMware Workstation 7.1.1 enables people to run multiple operating systems, simultaneously, one a single machine. Use the application to run different Windows operating systems as well as hosting a Linux based operating system, too. This makes it incredibly useful for users looking to test an OS, before fully installing on a host machine.

VMware Workstation 7.1.1 link. 

18 Aug 2010