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.
A virtual machine is nothing but a data file on a physical computer that can be moved and copied to another computer, just like a normal data file. The computers in the virtual environment use two types of file structures: one defining the hardware and the other defining the hard drive. The virtualization software, or the hypervisor, offers caching technology that can be used to cache changes to the virtual hardware or the virtual hard disk for writing at a later time. This technology enables a user to discard the changes done to the operating system, allowing it to boot from a known state.