Thank all of you for the responses. I asked those questions because,
as I said originally, it piqued my curiousity and i almost always get
fascinated with wondering how they do that. At some time in the
future, I might add aa second monitor to my gear, but that's not likely
to happen any time soon.

P.S.: @ VanguardLH, I use Windows 8.1 Pro 64-bit and am starting to
play around with virtual machines, pretty much out of curiosity
instead of for any real need. At the moment, I have successfully used
VirtualBox 6 to make VMs for Mint and Ubuntu 18.10 but am stuck trying
to make an android VM. I know VirtualBox doesn't support android, but
it's been interesting to see the YouTube videos showing that some
people have successfully made an android VM in VirtualBox. Just
requires more experimentation on my part.

John