Invisible doesn’t mean non-existant

Invisible doesn’t mean non-existant       Is because you don’t see a thing that this thing doesn’t exist?   This question can be one of faith or observation. We know that some things exist without being able to see them but with experimentation we can demonstrate that the thing really exists.   Now, is this because you deleted a file on your personal computer that the file is deleted? Depending of your settings, he will be in the garbage bin. So, if you empty the bin, will the file always exist? Obviously not. The file will always be there; only his reference in the file system will be deleted. Okay, if you rewrite on the file’s old sector and/or perform a low format on the hard drive; will the file be finally deleted and not recoverable? Unfortunately not. It will not be easy to recover the file but it will always be there; entirely or partially. Am I crazy? No. It will get time and resources but it’s possible. How? It’s the product of a phenomenon called residual magnetism. The subject gets in the news by ComputerWorld.com some weeks ago.                         If my memory is right, I read in Body of Secrets by James Bamford that the NSA is able to recover data on hard drives until between 5 to 7 low level formats. Is this freaky? Not if you don’t have state secret to hide. Remember, they need resources to recover these data. This is not easily done but it’s possible.               Some years ago you would have had been able to get unformatted hard drive in a governmental overstock outlets. Yes, and? You are asking. Think about it, which type of information your government is manipulating? Yes, mostly personal information. I remember that around 5 years ago the government of Quebec had been in trouble because citizen records have been found on old computers’ unformatted hard drives in such a store. This is a real problem. Is the income of a couple of dollars worth the embarrassment? I don’t think so. Are they always doing it? I don’t know; I haven’t been in such a store since then.               The best thing to do is destroying the hard drive, not selling it. You’ll get rid of all related possible problems. Check the price of a gig of storage space. Is the possible resulting problems worth the incomes? Personally I don’t think so.