The amount of work that you do on your computer at home can easily be backed up onto a CD-RW, CDROM, DVD or a memory stick. However, many organisations, such as school or an office, need to back up large pieces of data each day. CD-RW, DVD-RW or flash memory sticks are unlikely to be large enough for doing this.
Large organisations who need to back up their systems daily tend to use magnetic tapes to store their data.
Magnetic tapes can store up to one terabyte of uncompressed data - as much as can be stored on a hard disk.
Magnetic tape uses 'serial access' to find a piece of data. It works in much the same way as a video tape that you might have at home. To find a specific piece of data, you have to start at the beginning of the tape and continue fast forwarding until you get to the piece of data that you need. This makes it fairly slow to find and retrieve data so it would not be much use to store data that you needed to get hold of quickly. Magnetic tape is excellent for archiving data i.e. data not likely to be needed instantly.
Large companies such as a television network have robot storage libraries. This…