Did You Delete Those Files?

Most people delete files from their computers by dragging the file into the recycling bin and assuming that it's gone. A goodly number of people, however, understand that recycling is not the same as deleting, and so click on the command to "empty recycling bin" every so often. But even that is not necessarily enough. Although much of the technological wizardry performed on shows like CSI and NCIS is exaggerated, recovering deleted files is entirely possible and accurately (mostly) represented.

Files are simply strings of 0s and 1s stored in little memory cells on your computer's hard drive. A memory cell can never be "empty" -- it always has to be holding a 0 or a 1, whether or not it is meaningful. When you "delete" a file, the operating system simply lists the memory locations the file was using as available. In this way, it becomes ok for another file to use those memory locations, if they are needed. But if they are not needed, then the information that was there before you deleted the file is still there after you delete the file.

So, if you've done something bad and have files on your computer that might incriminate you, don't rely on your operating system to destroy those files. Instead, you can purchase (or, I'm sure, download) a program which will perform a "secure delete". In other words, it will not only allow the operating system to list the memory locations as available, but it will overwrite those meaningful 0s and 1s with meaningless 0s and 1s.

But criminal activity isn't the only reason to securely delete files. Many people set their old computers out at the curb or donate them to charity without ever realizing that files they deleted are still there for anyone with the right information to view. If you keep lists of passwords or accounts in a file on your computer, this can become valuable information in the hands of a thief. Before getting rid of your computer, you can either reformat the hard drive or securely delete your files. If it's going to a charity, it might be kinder to securely delete.