What is an incremental backup?

An incremental backup is defined as a backup that captures only the files and data that have changed since the last backup was performed, whether that was a full backup or another incremental backup. This method is efficient because it minimizes the amount of data that needs to be backed up at each session, which in turn reduces storage requirements and the time taken to complete the backup process.

For example, if a full backup is performed on a Sunday and incremental backups are taken on the following days of the week, each incremental backup will only include the data that has changed since the previous backup. This allows for quick restorations since only the last full backup and the subsequent incremental backups are needed to restore data to a certain point in time.

The other options describe different types of backups that do not align with the definition of an incremental backup. A full backup captures everything from the entire system, while a backup of every single file would suggest a complete backup, not just the modified files. Lastly, a backup that includes all files without incremental changes does not effectively reflect the concept of incrementality, as it does not focus on capturing only the most recent changes.