Formatting a drive does not erase data.
Formatting a drive erases file allocation information and performs other
housekeeping functions for data storage, but the formatting process does
not erase data from a drive.In PC operating systems deleting data is not enough. You need to wipe your data to ensure that it cannot be recovered.
Many people believe that when they delete a file, it is permanently erased. It is not. In actuality:
The data within the file still remains on your drive.
Evidence that the file existed still remains on your drive.
This is because of how an operating system saves and deletes files.
When you save a file, your PC stores the file name in a file allocation table. The data that actually makes up the file is saved directly on your computer's drive.
When you delete a file, the computer removes the reference of the file from the file allocation table, but the data still remains on the drive. The space occupied by that data is marked as "free space" and is available for overwriting by other newly saved files. The data remains on the drive until another file is saved over it (and even after overwriting, it might be possible to recover portions of the data).
Formatting a drive does not erase data.
Formatting a drive erases file allocation information and performs other
housekeeping functions for data storage, but the formatting process does
not erase data from a drive.
Even though you can't see the file (for example, through Windows Explorer), someone using easily available tools can recover the file and view its contents. This poses a significant security risk, and can lead to confidential information falling into the wrong hands.
Data wiping tools erase data by overwriting it with random characters. As you increase the number of overwrite passes, the greater your security. Each overwrite pass causes the data that previously occupied the location to become less "bright" than the random data that now rests on top of it.
Most undelete software tools recognize only the brightest, topmost layer, so one overwrite pass is sufficient. However, more advanced hardware extraction methods, such as an electron microscope, can often read up to seven layers down. This is why the U.S. Department of Defense standard is seven overwrite passes. DriveScrubber gives you the flexibility of tailoring the patterns used and the number of passes.
DriveScrubber also offers two options for data wiping: wiping all content from a drive or wiping just the free space. Both levels meet or exceed the standards of the U.S. Department of Defense (DOD 5220.22).
Wiping all contents completely erases all data beyond recovery. People find this useful if they are donating or giving away their computer and want absolutely no data to remain.
Wiping the free space erases just the data remnants and tracks left by deleted files. Existing files, programs, and the operating system are all left in intact. People find this useful for regular computer maintenance and security.
See Choosing the Right Wiping Method for more information.