I am told that when you delete stuff in the recycle bin that it remains somewhere on the computer. Is there a way to absolutely, totally delete and erase whatever you placed in the recycle bin? (Not that it applies but I’m told the investigative FBI and other agencies can reclaim what has been deleted) Thanks for sharing an answer.
Yes — To all the parts of the question. Data that has been deleted can be retrieved under the right conditions. And, yes, data can be irrevocably wiped out. Here’s how it all works.
Hard drives are like sand
First, you need to understand the nature of data. Documents, pictures, programs, etc. recorded on any medium is considered data. Writing data to a hard drive is not like writing on a piece of paper with a pencil that can be erased by turning the pencil over and vigorously rubbing the image until it disappears.
I equate the writing on a hard drive as writing on a sandy beach. You can rearrange the sand anytime you please to create new images. Therefore, erasing something on a hard drive is as easy as rearranging all the sand so that it does not make any sense.
Unfortunately, the images that get created on a hard drive have so much volume of ones and zeros (binary) that it makes more sense to leave the cleanup to the next program, picture, or document to be written, than to change each one of those ones and zeros into digital garbage.
What really happens behind the scenes is this: When a document is to be deleted from a hard drive, only the first “one” is changed into a “zero.” This is considered a digital semaphore. That is, a flag that lets the next program know that this “area” is available to be rearranged with ones and zeros.
The good thing is that if you accidentally deleted an important document, there are programs that can go and find the “flag” and turn that “zero” back to a “one” and voila, your file is back intact.
That is why dumb criminals get caught with illicit material in their computers. Even though they have “deleted” the questionable files, the deletions are usually in haste and at the last minute. Leaving all the data in pristine condition for retrieval.
One way to permanently delete your files is to overwrite them with other stuff. The bad news is that if you have deleted a file accidentally, there is a good chance you will permanently destroy the document because the flag said it was ok to do so.