Have you ever deleted a data/file either by mistake or on purpose, and wished you could reverse it but it appears it is already too late? That could also occur when the system crashes or you encountered a malware attack.
How Delete Works
Deleting is simply the process of removing the "path" or reference to access a particular file or data, leaving the space free for other data to be copied in the place. Therefore the computer or device could no longer read the deleted file.
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When you delete in some device, it simply enters the recycle bin where you can simply go to either restore/retrieve it or erase it from the system. But what if you had deleted in both the device and the recycle bin?
Are Deleted Files Gone?
Deleting is analogous to a library index card. This card simply shows us where the books are located. You have the science section, the public records, the art section, etc. You can locate any of books in this library using this index card. Deleting is throwing away this index card. The books (files) are still there but you can no longer access it ( the device cannot read it) since the card index system (directory or path) is missing.
Since the files are still there you could retrieve or undelete the deleted files by going to the directory and retrieving it.
Why Not Fully Delete Files?
It is simple, a computer finds it easier to remove reference to files instead of to overwrite it with other data to avoid recovery.
The Good and The Bad
It is a good thing that you can recover mistakenly deleted important deleted file or folders. The bad is that sensitive data/ financial records on your hard drive/memory that you deleted can be recovered by data retrieval method! I know a paranoid man that never resells his phone or PC for fear someone may retrieve some deleted data on it. One of such deleted file recovering software is called recuva,etc.
Making Sure Data Deleted Are Never Retrieved
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The idea here is to overwrite the deleted files with zeros or other trash just to make sure the original file is no longer recoverable. This is called a low-level format and there is special file shredders software that would make sure that a file cannot be retrieved. Some examples of such software include Eraser (free software), Secure Shreder (free software), Secure Eraser (free and premium version), etc.
Disclaimer: The author does not endorse or guarantee any software above to work. This is for educational purposes as he shares no affiliation with the developers. Thank you.
