Users are often confused as to the terminology used concerning data backup and restore.

Backup and Restore

In information technology, a backup, or the process of backing up, refers to the copying and archiving of computer data so it may be used to restore the original after a data loss event.
From https://en.wikipedia.org/wiki/Backup

This expects an existing data backup, which can be restored. Restore refers to the standard process of restoring a system to expected functionality using a previously created backup data set.

Rescue and Recover

In computing, data recovery is a process of salvaging inaccessible data from damaged, failed, corrupted, or inaccessible secondary storage media when it cannot be accessed normally.
From https://en.wikipedia.org/wiki/Data_recovery

The terminology used is intentionally dramatic as it indicates a massive management failure to implement the required level of care to keep operational data secure, and have a working backup system in place.

Rescue and Recovery of data implies an abnormal situation. It indicates that no working backup is available and extraordinary steps are required to return the system to full functional capability. This often refers to broken or damaged hardware, but may also refer to malicious damage, such as that caused by intentional user action or virus software. An example of non-malicious intentional user activity may include deleting of files where those files should not have been deleted.

Not having a backup means a data restore will not be possible, and it is required to engage in rescue and recovery activities. In addition Reconstruction will be necessary. As data has to be salvaged, it is to be expected that gaps in the data will be present. These gaps may not be initially apparent. Reconstruction refers to re-work and re-creating data, so that the final version of the re-created data corresponds to the now-absent previously existing data. Reconstruction effectively requires allocation of resources to re-do and re-work tasks that were completed previously. Experience has shown that such re-worked products never meet expectations.

Where a Last Known Good Backup exists, this may simply be used to Restore a system to a previous point in time. Where no such backup exists it becomes necessary to engage data rescue and recovery experts to attempt a data salvage process.

How many R’s in in backup?
• Backup = Restore
• No Backup = Rescue, Recover, Reconstruct