Methods of erasing
You can select a method of erasing from the following:
NSA
Data is overwritten twice with random numbers and once with zeros.
DoD
Data is overwritten by a random number, then by its complement, then by another random number, and is then verified.
Random Numbers
Data is overwritten multiple times with random numbers. The number of overwrites can be selected from 1 to 9.
BSI/VSITR
Data is overwritten 7 times with the following patterns: 0x00, 0xFF, 0x00, 0xFF, 0x00, 0xFF, 0xAA.
Secure Erase
Data is overwritten using an algorithm that is built in to the hard disk drive.
Format
The hard disk is formatted. Data is not overwritten.
The default method for erasing is "Random Numbers", and the default number of overwrites is 3.
NSA stands for "National Security Agency", U.S.A.
DoD stands for "Department of Defense", U.S.A.
If your machine is equipped with the Enhanced Security HDD Option, the hard disk automatically discards the encryption key, making it impossible to decrypt the data on the hard disk before the data is erased using the selected method.