How peoples change and edit windows?

I have seen the sevral windows that has been changed completely. Like here in Pakistan a province Balochistan, I saw a window that has been named as Baloch windows. I installed that and saw they had chaned each and every thing of the windows. Even they had changed the windows logo, the specific names that we cant change like Computer,Recycle Bin, Control Panel, Start and All Programs etc etc. There was nothing like the windows but all changed and edited. Even the theme was changed even each and every thing. Can somebody tell me how these people do this?
Asked Jun 17, 2013

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