CompTIA: Advanced Security Practitioner (CASP) Exam Prep

Answer: D - An incremental backup backs up files that have changed since the last full or partial backup.

Key Takeaway: During an incremental backup, only the files changed since the most recent backup are included. The time it takes to execute the backup is much less than the time it takes to perform a full backup. An incremental backup is the fastest backup and requires the least storage space on the backup media. However, incremental backups also require the longest time and the most tapes to restore. A differential backup is a backup containing all of the cumulative changes since the last full back up. Therefore, a differential is easier to restore than an incremental, but lengthier to back up as the amount of time since the last full backup increases.