What Really Happens When You Delete Something From Your PC

If you want to sell or dispose of your computer, it’s important to make sure there isn’t any data left on there for someone to find. When it comes to NTFS-formatted hard drives, simply deleting your files isn’t enough.

When you “delete” a file, it gets moved to the trash or bin in your operating system. However, as Linus from the Techquickie YouTube channel explains, emptying the trash or bin doesn’t remove that data. The only thing removed when you empty the trash or recycle bin is the master file table reference, which merely tells the operating system where the file was located. Essentially, you’re only removing the map to the data — not the data itself — while also giving the operating system permission to overwrite that area of the hard drive. This is why some data is recoverable with special software or the right set of skills.

Lingering data is not something you want if you’re selling or giving your system away, so there are a couple options you have to ensure your data stays truly deleted:

• Delete and rewrite: You delete all of the data on the hard drive to the best of your ability and then rewrite over the old data with new random data over and over again. There are a number of tools that will do this for you.
• Physical destruction: You destroy the hard drive to the best of your ability. Boom. Obviously, this is not ideal if you want to sell your hard drive, but it is the one way to be absolutely sure your data is safe.

For a lot of you, this isn’t new information, but Linus does a great job of laying it out, so it’s a good explanation for tech beginners. Check out the full video above for more.

What Happens to Deleted Data as Fast As Possible [Techquickie/YouTube]