The IBM System/360, released in 1964, introduced what is now generally known as 9 track tape. As with the earlier IBM 7 track format it replaced, the magnetic tape is ½ inch (12.7 mm) wide, but has 8 data tracks and one parity track for a total of 9 parallel tracks. Data is stored as 8-bit characters, spanning the full width of the tape (including the parity bit). Various recording methods are used to place the data on tape, depending on the tape speed and data density, including PE (phase encoding), GCR (group code recording) and NRZI (non-return-to-zero, inverted, sometimes pronounced "nur-zee"). Tapes came in various sizes up to 3,600 feet (1,100 m) in length.
The standard size of a byte was effectively set at 8 bits with the S/360 and 9 track tape.
For over 30 years the format dominated offline storage and data transfer, but by the end of the 20th century it was obsolete, and the last manufacturer of tapes ceased production in early 2002, with drive production ending the next year.
Read more about 9 Track Tape: Typical Operation, Technical Details, IBM Generations, Examples, Standards, Other Drive Manufacturers, Media Manufacturers
Famous quotes containing the words track and/or tape:
“It is remarkable how easily and insensibly we fall into a particular route, and make a beaten track for ourselves. I had not lived there a week before my feet wore a path from my door to the pond-side; and though it is five or six years since I trod it, it is still quite distinct. It is true, I fear, that others may have fallen into it, and so helped to keep it open.”
—Henry David Thoreau (1817–1862)
“We shall see but little way if we require to understand what we see. How few things can a man measure with the tape of his understanding! How many greater things might he be seeing in the meanwhile!”
—Henry David Thoreau (1817–1862)