4e9fe054_Implementing_a_backup_strategy_able_1___BACKUP_DEVICE_OPTIONS_Target_backup_device
[Advantages] Easy Very fast Files not lost if master drive crashes or becomes unbootable Drive containing backup can be removed easily so that it is then completely isolated from possibility of infection by malware Drive can be stored in a safe location or off-site If the backup is a clone of the master drive or an active primary bootable partition from the master drive, the PC can be booted directly from the drive in the caddy. (10) [Disadvantages] Cost of hardware (3) Small fan in the caddy's cradle could be a tad noisy (4) but is essential to keep the drive at a safe temperature In some caddies, the plug at the rear of the caddy might not mate tightly with the socket at the rear of the cradle (5) Requires a vacant CD/DVD type bay in the PC. [Target backup device] 
Drive in removable caddy (aka 'mobile rack') (9)
Implementing a backup strategy
Target backup device