Backup copy

In the field of information technology, a backup copy (or backup) is an exact copy of data or software that can be used to restore the original in case of a system crash or other event that causes loss or damage to data or software. Backup copies are useful primarily for two purposes:


 * To restore a state following a disaster (called disaster recovery) or * To restore a small numbers of files or software modules after they have been accidentally deleted or corrupted.