How to find the Tape,disk and Virtual device(device types) backups  in Sql server:
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All device types of backups  information stored on  Msdb database in  Backupmediafamily table.

To find disk backups:

Use Msdb
Select * from  backupmediafamily where device_type =2

Tape:

Use Msdb
Select * from backupmediafamily where device_type=5

Virtual device:

Use Msdb
Select * from backupmediafamily where device_type=7

 permanent backup device:
Use Msdb
Select * from Backupmediafamily where device_type=105