A tape library is a device which houses multiple tape drives, multiple tape cartridges and the robotics
to automatically load and unload the cartridges in and out of the drives. Tape libraries, sometimes
referred to as jukeboxes, are similar to autoloaders in that with software they will automatically
replace a "full" cartridge with an empty to complete a backup but they also allow the use of multiple
drives simultaneously. Using multiple drives provides several advantages including the ability to
perform multiple backup/restore jobs at the same time as well as increased speed. A tape library's
potential maximum throughput is directly related to the type and number of tape drives it houses. We
say potential here because real life throughput rates are also effected by host systems and networks.
Barcode scanners are typically standard equipment on tape libraries though they are options on some
autoloaders. A barcode scanner allows for much faster access to data contained on a particular data
cartridge. Instead of loading each tape into a drive to read the tape's information to see if the data is
there, backup software will keep track of which tape has the data based on a barcode number.