[PLUG] Two monitors, two applications

[Rich Shepard]

Running Slackware-14.2/x86_64 with xfce4-4.12.0. When the new FHD portable
montitor arrives and I connect it to the desktop, can I configure it
(perhaps using randr?) to display two different virtual desktops rather than
mirroring the main monitor?

I'd like to run the teleprompter software on the portable monitor while
running OBS and associated windows on the main monitor.

My web searches suggest this is possible and I need guidance on what to read
to learn how to configure them this way.

TIA,

Rich