WARNING: By doing the following you will permanently delete your data and it will not be recoverable!
Why Do You Want to Securely Delete
Computers are now part of every day life. We use them for work, school, entertainment and for personal reasons.
The data on your hard drive is information and depending on who has access to it, will consider it very valuable.
People can do all sorts of things with your data which might hurt you. To stay protected it can be a good idea (depending what is on your computer) to delete the information you are no longer using or do not want any one else to have.
What is the Difference Between Normal and Secure Deletion
When you delete something from your computer, its it not really gone.
Even tough you can no longer see it, with the right tools, someone can get it back. That is because when you delete your data normally, it is still really there, but your computer has actually marked that space to be written over on in the future with future files.
If you want to delete your data permanently, you need to securely delete with the aid of an application that will rewrite over your data multiple times, so basically shred the information so no one can get it back.
Secure Delete on Windows
Eraser is a great free Windows program which works with all versions of Windows.
Once you open the application all you have to do is direct it to the file or folder you want to permanently delete and it will write over it multiple times with random data so no one else will be able to read it.
Eraser also has a tool which you can use to schedule erasing of certain parts of your computer periodically in case you forget or in case someone else has access or steels your computer.
Secure Delete on Mac
Apple Macs can use a program called File Shredder which can be used on most Macs and Macbooks and downloaded from the Apple App store completely free.
The easiest way to use this program is to put it in your doc at the bottom of your computer and anytime you want to delete a file or folder just drag it into the App.
You can also decide in preferences who many times you want the data to be written over.
The more times you have the data written over, the longer it will take and the more secure it will be and harder for someone to recover it.
Secure Delete on Linux
Linux is a little more complicated and it depends on what version of Linux you are using etc.
Unlike Windows a lot of the Linux distributions use command line which involved typing a list of commands rather than clicking on icons and executions.
Shred is an excellent choice to use for Linux.
In Ubuntu Shell type the command: sudo apt-get install secure-delete
This will install the utilty. Once you know the file you would like to destroy the best command is: shred -zvu -n 5 <file name>