An 
Object-oriented operating system is an 
operating system that uses the concept of 
WIMP (Windows, Icons, Menus, Pointer or Windows, Icons, Mouse and Pull-down Menus depending on your text). Such systems use an XY pointing device like a 
mouse to direct a cursor (pointer) on the 
screen. Most, if not all, desired actions are achieviable by manipulation of objects on screen through the WIMP concept.
Windows and Mac OS are two commonly used examples of object-oriented operating systems.
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