Hermit's Free Library Computer Security
Hermit's Free Library Computer Security
Complete description of the five most common types of data backup: Full, Incremental, Differential, Daily Copy, and Copy.
Dedicated backup software commonly includes the following types of backups.
| Type of backup | Files backed up | Files marked as backed up | Media volume required | Notes |
| Full | All selected files even if they have changed since the previous backup of any kind. | All files marked as having been backed up. | High |
Always first backup in a backup cycle Uncomplicated to restore |
| Incremental | All selected files which have been created or modified since the last backup of any kind. | Copied files are marked as having been backed up. | Relatively low | Must be restored in exact order of creation after restoring full backup. |
| Differential | All selected files which have been created or modified since the last full backup. | Does not mark copied files as having been backed up. | Relatively high | Should not be mixed with incremental backups. Only most recent need be restored after restoring full backup. |
| Daily copy | All selected files which have been created or modified on the current day. | Does not mark files as having been backed up. | Relatively low | Must be performed every day. Must be restored in exact order of creation after restoring full backup. |
| Copy | Backs up all selected files. | Does not mark files as having been backed up. | High | Used most often to copy files from one computer to another. |
