Gaurav,

But lets not forget that since the verry beginning, when Bill Gates and Steve Ballmer were not so rich and they were only tech savvy college sophomores, they have contributed a lot in the field... GUI interface was first thought of by them.. thats a different issue that Linux flavours followed the line and introduced XWindows system...
I'm not going to correct all of your Microsoft statements, I'll stick to one.

- X was released in 1984, around the same time as Windows 1.0 (announced in november 1983, released in 1985). You can't really say that Linux followed, as you don't develop a whole graphical environment just like that.

- Apple released the Lisa in 1979, including GUI

- Xerox released the Alto in 1973, including GUI

- First mouse and GUI used in the 1960's

Here is an interesting article for you:

A History of the GUI

I won't go into Microsoft bashing, but Bill Gates and Steve Ballmer have mainly excelled at buying (or stealing in the case of Windows) ideas or products from others. They visited Apple to get the Windows idea.

Cheers,

BrainStop