Toshiba Satellite M50 (PSM53) - Manual (Page 100)

TOSHIBA M50 4-32
Operating Basics
Setting up more than one display
You can set up your computer to utilize more than one display, effectively
spreading a single desktop screen across two monitors.
The Display Properties window allows you to adjust more precisely the
relative positioning of the two displays when they are configured as an
extended desktop. On the Display Properties window, the two displays can
be positioned horizontally, vertically or in any diagonal configuration you
wish, as shown below.
If an external display will not be connected next time you use your computer,
you should cancel any extended desktop or clone display settings before
shutting down your computer.
Clone display settings are those where more than one device has been
selected and is simultaneously applicable.