Which type of backup should a customer use that compares and saves changes from the last full backup?

The type of backup that compares and saves changes from the last full backup is known as a differential backup. In this method, after a full backup has been completed, any changes made to the data since that last full backup are recorded in subsequent differential backups. This means that each differential backup will include all the changes since the most recent full backup, making it easier to restore the data to its state after that full backup.

Differential backups are beneficial because they allow for a quicker recovery compared to having to restore multiple incremental backups. A differential backup requires the original full backup and the latest differential backup to restore the data, which simplifies the backup management process when time is of the essence.

In contrast, a full backup creates a copy of the entire dataset every time it runs, and a clone is an exact replica of a system or data in its entirety, rather than just the changes. Incremental backups only save the changes made since the last backup of any type, meaning they require more management during restoration since each incremental backup must be processed in order.