In information technology, Global backup support refers to making copies of data so that these additional copies may be used to restore the original after a data loss event. These additional copies are typically called "backups."

Due to a considerable overlap in technology, backups and backup systems are frequently confused with archives and fault-tolerant systems. Backups differ from archives in the sense that archives are the primary copy of data and backups are a secondary copy of data.

1. On-line 
   ITSL provides online Backup facility is the most accessible type of data storage, which can begin restore in milliseconds time. A good example would be an internal hard disk or a disk array (maybe connected to SAN).
   
   
2. Near-line 
   Near-line storage is typically less accessible and less expensive than on-line storage, but still useful for backup data storage. A good example would be a tape library with restore times ranging from seconds to a few minutes.
   
   
3. Off-line 
   Off-line storage is similar to near-line, except it requires human interaction to make storage media available. This can be as simple as storing backup tapes in a file cabinet. Media access time is more than an hour.
   
   
4. Off-site vault 
   To protect against a disaster or other site-specific problem, many people choose to send backup media to an off-site vault.