A VM or "virtual machine" is a type of computer program that creates an emulated software environment. Not that any real person actually knows what that means.
Think of it as a sort of a computer that runs on another computer. You can run multiple "virtual machines" on a single computer; then you give access to individual "VM" to all your clients or employees. Busy executives like yourself love VMs because it saves them so much money on hardware; why waste money on 100 servers when you can just buy one and make it look like you have 100 computers! All your peons down in IT would probably recommend against running it on Windows8, but that's just because they like running complicated things like Linux. Windows 8 can handle VMs just fine, and - thanks to its colorful and touch-friendly interface - it's so easy to use that you can fire all those overpaid geeks and have your secretary handle everything for you. Think of the cost savings!