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 can be unplugged easily so that it is then completely isolated from possibility of infection by malware [Disadvantages] Additional cost if drive does not already exist Small capacity Ties up an expensive device (in terms of $ per Mb) which is much more applicable for other purposes. [Target backup device] 
Thumb Drive (aka Flash Drive, Pen Drive)
Implementing a backup strategy
Target backup device