What is "+" on mouse cursor?

[David Niemi]

On Tue, 2005-11-15 at 11:31 +0000, Andy Green wrote:
> David Niemi wrote:
> 
> > OK, Ctrl-Alt-F1'd logged in as root, killed gcalculator PID 30750, and
> > typed "exit" which logged me out and I am now back at a login prompt,
> > how do I get back to my running X session.  
> > 
> > Kinda dumb question I know but I never needed to do this before so
> > didn't learn it yet!
> 
> I remember well the exact same puzzle :-0
> 
> Ctrl-Alt-F7
> 

Yup that worked, I didn't want to try finding this by trial and error,
having enough fun with whatever I did to get the "+" sign.  What causes
that?

Also, for future reference what is it called when one Ctrl-Alt-F1's or
Ctrl-Alt-F7's?