Google for KILLDISK or DBAN, both have free versions. Print any details or instructions. I suggest you get the .ISO file in order to burn to disc and thus boot from it and start the process to "wipe out" you HD as required. The pgms. I mentioned are pretty much the most common out there and do the job well. good luck
Actually I am going to sell my hard disk so i want to format it so that its data can't to recovered.??

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