When you delete a file from your computer, that file is probably not quite as deleted as you might think it is.

There's an entire industry predicated on recovering data that was intentionally or unintentionally

trashed on a user's desktop or on their laptop, their smartphone, their tablet, or any other

device with a hard drive and an operating system, which is pretty much all of them these days.

The reason these files can often be recovered, even after we put them in the trash and empty the

trash, and seemingly eliminate them from our lives, from existence, is that hard drives do not

work the way that most people suspect they do. When you delete a file from a hard drive,

it pretty much just moves that file to another part of the drive

that is more or less inaccessible to the user.

And the idea is that someday, if and when

the drive runs out of free space,

it begins to overwrite that space

that is currently filled with all the stuff that you deleted.

It shows up as being free if you ask the operating system, but there's a bunch of trash there,

just waiting to be overwritten by new data eventually.

And that's what these file recovery services take advantage of.

They go looking in those unindexed portions of your

hard drive, almost like they were searching through parts of an old library that was declared off

limits years ago. There's no information in the card catalog saying anything about books

back in that derelict old part of the building, but it's actually

where all the discarded books are kept.

And if you search those supposedly empty shelves, you might stumble across something you thought

...