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To restore the last delete operation that has taken place. There may be more than one level of undelete, allowing several or all previous deletions to be restored. Files in Windows and Mac can generally be undeleted because they are only moved to the recycle bin or trash can when they are deleted in an application or file manager. See file wipe.

file wipe

A security measure when selling, giving away or retiring a computer. A file wipe completely erases the data from the hard disk.

Deleting Does Not Erase
When a file is deleted in an application or file manager, only the file name in the directory is marked as deleted. The data still reside in the disk sectors until overwritten by new data by the same or some other application. In the meantime, if somebody wanted the file badly enough, it can be reconstructed from the sector data.

Wipe Means Write
Wiping the hard disk means actually erasing the data in the disk sectors. For maximum security, experts claim that random data should be written into the sectors several times, because forensic analysis can detect the previous magnetic residue if the magnetic bits are overwritten only once. In addition, caches such as the recycle bin and trash can are also cleared. See wipe.

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Before/After Your Search Term
unbundleundelivered email
unbundlingundelivered mail
UNCunder cover removal
uncached speedunderbanked
unchecked bufferunderflow
unconditional branchUndernet
undefined variableunderscore

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