7.8   MAGNETIC TAPE

Magnetic tape is the oldest and most cost-effective of all mass storage devices. While it is used less and less, many businesses still use magnetic tape for archiving. First-generation magnetic tapes were made of the same material used by analog tape recorders. A cellulose-acetate film one-half inch wide (1.25cm) was coated on one side with a magnetic oxide. Twelve hundred feet of this material were wound onto a reel, which then could be hand-threaded on a tape drive. These tape drives were approximately the size of a small refrigerator. Early tapes had capacities under 11MB and required nearly half an hour to read or write the entire reel.

Data was written across the tape one byte at a time, creating one track for each ...

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