An incremental backup is designed to be efficient by capturing only the data that has been created or modified since the last backup was performed, regardless of whether that last backup was a full or a previous incremental one. This process typically involves checking and then resetting a file's archive bit to mark it as backed up. While this method results in the fastest backup times and smallest storage footprint for daily operations, a full restoration requires the last full backup and every subsequent incremental backup file, which can complicate and lengthen the recovery process.

A. Differential backup: This method backs up all data that has changed since the last full backup, not the most recent backup of any type.
C. Daily backup: This backs up files based on the modification date (e.g., all files modified today), not in relation to the last backup event.
D. Full backup: This method backs up all selected data, irrespective of any changes since the previous backup.

1. National Institute of Standards and Technology (NIST). (2010). SP 800-34 Rev. 1

Contingency Planning Guide for Federal Information Systems. Page 40 (Section 4.3.2). "Incremental backup—a copy of all files that have changed since the last full or incremental backup."

2. Carnegie Mellon University Information Security Office. (n.d.). Data Backup Options. Retrieved from https://www.cmu.edu/iso/governance/guidelines/data-backup.html. The guideline states

"Incremental Backup: Backs up only the data that has changed since the last backup (of any kind)."

3. Silberschatz

A.

Galvin

P. B.

& Gagne

G. (2018). Operating System Concepts (10th ed.). Wiley. In Chapter 12

Section 12.7.2

"Backup and Restore

" it is defined that "An incremental backup copies only the files that have changed since the last partial backup."