Incremental Backup

Backup programs generally give you two options: full or incremental.

A full backup will save everything from the active media to the backup media. This type of backup does not take into account the fact that many files don't change from backup to backup.

An incremental backup solves this problem by only backing up the files that have changed from the last backup. While this saves space on the backup media, it makes restoring the data more difficult as the full backup has to be first restored and then the various incremental backups restored in sequence in order to perform a full restore. This can result in extra files restored; files that were deleted between the full restore and the last incremental backup.

Some programs will solve this problem by making a catalog of all of the files in the full and incremental backup files and then use that catalog to restore only the latest versions of files.

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