Spanned or Normal: A data in more than one location.

RAID (Redudant Array of Disks): A more controlled data back up that often makes the computer faster as it is managed by the system by user design.

True Back up: To hold the data off of the origin or same system or in idealistic reality to hold it in a fully different location such as another room or facility. Required for important data such as government or schooling records. Sounds simple, but it is a term that should always be in effect.