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(SPOOL) Accessing peripheraldevices with the help of an off-line tape drive. The termwas derived by IBM for use with the IBM 360 operatingsystems.In the early days of computing (early 1960s), beforemultitasking was invented, computers (e.g. IBM 704) couldrun only one job at a time. As peripheral devices such asprinters or card readers were much slower than the CPU,devoting the computer (the only computer in many cases) tocontrolling such devices was impractical.To free the CPU for useful work, the output was sent to amagnetic tape drive, which was much faster than a printerand much cheaper than a computer. After the job was finishedthe tape was removed from the tape drive attached to thecomputer and mounted on a tape drive connected to a printer(such as the IBM 1403). The printer could then print thedata without holding up the computer. Similarly, instead ofinputting the program from the card reader it was first copiedto a tape and the tape was read by the computer.