You got a .rar file and you don't how to open it, some one asked you to send him "a rar file" or you just need a good archiving software? Download and install WinRAR.
The way this fearless man is playing with a 8 foot (2.5 meters) beast of a grizzly bear, like you would play with a tame golden retriever is nothing short of amazing.
If you want to make a clean install of the new OS X Mavericks or even the older versions of Mac OS X, than I strongly suggest you to create a bootable OS X key or a drive.
Speculating about future is is most of the time futile, let alone about the distant 100,000 years kind of future. But we can always guess and if there is science involved we even might be onto something.
