VDI Vs. Local Desktops? What technology makes VDI possible? and why would someone need VDI?

Hello,

Suppose you have a company with500 users. With VDI you won't have to buy500 Computer Units which will cost you a fortune. Also, if your500 employees need a specific application, lets say Microsoft word you won't have to buy500 licences. You only buy ONE license and share the application with VDI.  What makes VDI possible are the Virtulization Technologies such as Hyper-V, VMware, ... 

So, VDI will save you a lot of money and space.