Orient yourself to the weatherboards you'll be working with: the board you're replacing, the board immediately above it and the one immediately below it. Call the board above the one you're replacing board A.. Board B is the board that you're replacing.
Desktop virtualization is the concept of separating the logical desktop from the physical machine. One form of desktop virtualization, virtual desktop infrastructure (VDI), can be thought of as a more advanced form of hardware virtualization.
Desktop virtualization and VDI mean pretty much the same thing VMware was first to promote the VDI (virtual desktop infrastructure) terminology, but Microsoft and Citrix have followed suit, offering VDI solutions of their own based on the Hyper-V and XenServer hypervisors, respectively.