Disk Scrubber

Privacy tools called disk scrubbers are used to make sure that data deleted from the hard disk of a computer cannot be recovered. This is particularly useful when users wish to sell their laptops or hard drives; a user's confidential data should not be recoverable by the new owners.

When files are deleted from the computer, they go to the Trash Can or the Recycle Bin. They can be recovered from here by the "undelete" operation. Many users are under the impression that deleting files from the Trash Can or Recycle Bin will erase files forever, and that these files cannot be recovered and read, but this is not true. Using certain techniques, it is possible for skilled users to recover data that appear to be erased. Until the erased data is overwritten with something else, it can still be recovered.

In order to ensure that deleted data is truly not recoverable, tools called disk scrubbers or drive scrubbers overwrite deleted data with a random pattern of data that does not make any sense. This operation is called wiping. After wiping the hard disk, it is not usually possible to retrieve the old data; however, disk scrubbing tools are not perfect. It is still possible, although not easy, to recover data from wiped drives.

Some common tools used for disk scrubbing are Windows Washer  , Eraser  , and Evidence Neutralizer  .