Fred:
...
> I don't understand what you mean by virtual terminal.

There are not many "true" terminals left:

https://en.wikipedia.org/wiki/Computer_terminal

so basically all terminals today are virtual, in the sense that
they behave as if they were an actual terminal, but they are not.

There are basically two types of virtual terminals:

. virtual consoles (also called virtual terminals)
https://en.wikipedia.org/wiki/Virtual_console

. terminal emulators (like xterm)
https://en.wikipedia.org/wiki/Terminal_emulator

It seems the primary differance between them is that the virtual
consoles/terminals works in the text mode which linux comes up in.
I.e. with no X11, wayland, openbox or whatever graphical support.

And the terminal emulators works in the graphical mode.

Some people relate this to the difference between DOS and MS-Windows.

Regards,
/Karl Hammar