You can delete a file without erasing it, erase a drive without wiping it, shred a file without deleting it, and wipe hundreds of files at once… that were already deleted.
Confused? I’m not surprised! These four terms – wipe, shred, delete, and erase – might sometimes be used interchangeably but they shouldn’t be.
Delete: “Hide Me, but I’ll Be Here If You Really Need Me”
The word delete is one we use a lot. A coworker asks if you still have that document on your tablet and you say “I deleted it” or your friend asks if you’ve “deleted” that photo of him from the party last night.
It’s even entered the common lexicon – my son told me once that he “deleted” his gum wrapper. I’m serious (he had thrown it away). It’s synonymous with “get rid of” but in reality, that’s anything but true.
Here’s the truth: when you delete something, be it on your computer, smartphone, digital camera, or anywhere else, you don’t remove it from existence, you just hide it from yourself. The actual data that makes up whatever you deleted is still there.
Deleted files, especially ones that were recently deleted, are easy to get back with data recovery software, much of which is freely available online.
In summary: when you delete a file, you don’t erase it, you just make it hard to find.
If you want to truly erase data, you’ll need to actually erase the data.
Erase: “Are You Sure? You’ll NEVER See Me Again!”
The term erase is what most of us are probably after when we get rid of, or try to get rid of, files.
There are three generally accepted ways to erase data: wipe or scrub it using a special program designed to do such, disrupt the magnetic field of whatever thing is storing the data, or physically destroy the device.
Unless you never want to use the hard drive, memory card, flash drive, or whatnot again, the first method – wiping or scrubbing the data – is what you’ll want to do.
In summary: when you erase a file, you make it impossible to get back.
In many ways, wiping data and scrubbing data are identical ways of erasing data. The main difference between the two is the scope of the erasing…
Wipe: “I’m Going to Erase EVERYTHING”
When you wipe a hard drive, or some other storage device, you erase everything that’s currently on it, as well as anything you’ve previously deleted that might still exist.
Programs that can wipe entire drives are often referred to as data destruction software programs. They work by overwriting every divisible part of the drive, used or otherwise, via one of several data sanitization methods.
In summary: when you wipe a drive, you completely and permanently erase everything on it.
See my How to Wipe a Hard Drive tutorial for a full walkthorugh of this process, something I recommend you do before you sell or give away your computer or hard drive.
Shred: “I’m Going to Erase This, and Only This”
When you shred a piece of data, usually one or more files or folders, you erase whatever it is you selected, and only those items.
Shredding individual files, like wiping entire drives, erases data by overwriting the space with some pattern of 1’s and 0’s. Programs that do this are called file shredder programs and there are many free ones available.
In summary: when you shred files, you completely and permanently erase them.
Because shredding is something you can do whenever you want to, on a small collection of files, file shredder tools are often installed and used on a regular basis as way to really erase whatever it is you’d otherwise delete.
What About Formatting? Does it Delete or Erase Data?
If you’ve ever formatted a drive before, you might have been under the impression that it’s one way to truly erase a drive. That may or may not have been the correct impression.
In any version of Windows, a quick format is always a fancy way of deleting – not erasing – the files on the drive. That’s part of the reason it’s so fast!
In Windows XP, the format process, no matter how you do it, is just a whole-drive-delete. The reason a normal format takes so long is because it’s checking the drive for issues.
In Windows 10, Windows 8, Windows 7, and Windows Vista, a normal (non-quick) format automatically does a one-pass, write-zero overwriting of data – a very simple wipe, and probably just fine unless you work for the NSA. See How to Format a Hard Drive for a full tutorial.
Source : https://www.lifewire.com/how-to-wipe-a-hard-drive-2624527