Even if you delete or format your disk , someone can find your data!

I saw a video the other day, of a guy that could take a USB or a hard drive that already is being format, and even if you open it and see that there is nothing inside , with specific programs he actually recover the lost data! It surprised me a lot so i did a little research about this subject

Imagine the scenario that you are giving away your computer , deleting all the Highly secretive data (naked pictures, paypal codes , bank account , NASA alien research ) from your disk , they are not actually deleted! They are just marked as deleted and become invisible to Operating System . The data are still in the disk and are overwritten by the time (this happen so the disk will work faster)

Maybe for you its not too important to destroy the data because you are smart and you don't safe anything on your computer but imagine the passwords you used to log in in your bank account , the passwords you used in steemit if you are connecting automatically
For huge companies that they spend millions of dollars to protect their data from hackers , and it will cost them billions of dollars damage if they end up in the wrong hands , it is very important !

I can understand the value of deleting the data from the drive, but how i do it?
How i delete the data "Permanently" ?

Solution 1:
Delete the data one by one
It is a great method if you wish to delete selected data . However , if you have a lot of data to delete, then this is no the solution for you because you might miss out some data (passwords , temp files and in general data that are not present right in front of you)
To do that, you need to download a program as File Shredder that is completely free and simple to use

Solution 2:
"Rewrite" on the data that are already in the disk
To do that, a cool program is DBAN by Blancco that it basically rewrite on your drive with pseudorandom numbers to make it reaaaally hard to recover personal data
Before you do that, make sure you back up all your important data in a CD because there is no turning back ! IF YOU HAVE YOUR OPERATING SYSTEM INSTALL IN THIS DRIVE, BE CAREFUL BECAUSE YOU WILL ALSO LOSE THAT

Solution 3 :
My favorite one
DESTROY the hard drive!
You dont need any program to install . The only thing you need is a hammer, or a rock (free tool) or even your powerful fist .
You can also use your imagination with this one ;)