What Are The Main Purposes Of Mac Os And Windows Xp?

Both serve as an interface between the computers and the people who wish to use them.  Just like the driver's seat in an automobile - without the steering wheel, pedals, turn signals, defrosters, mirrors and other devices in the car's cockpit, a driver would have a difficult time "interfacing" or controlling the car he or she is driving.  And just like auto manufacturers, those who write Windows XP, Mac OS and Linux and other operating systems have their own ideas of what those interfaces should look like.