What type of backup includes all data, regardless of when it was last backed up?

A full backup encompasses all the data within a system at the time the backup is made, regardless of any prior backup activity. This type of backup captures all files, applications, and system settings, allowing for a comprehensive restoration point should data loss occur.

The advantage of a full backup lies in its simplicity; it ensures that all necessary data is collected in one operation, making it easier to restore when needed. A full backup provides a complete snapshot of the data environment, which is vital for disaster recovery and ensures that nothing is overlooked.

Incremental backups, on the other hand, only save changes made since the last backup. Differential backups save changes since the last full backup. Mirror backups create an exact replica of the data but may not include historical versions of files. Thus, these alternatives do not provide the complete coverage that a full backup offers, which is why the latter is the correct choice in this context.