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Punched tape is an old-fashioned form of data storage, consisting of a long strip of paper in which holes are punched to store data.
The earliest forms of punched tape come from weaving looms and embroidery, where cards with simple instructions about a machine's intended movements were first fed individually as instructions, then controlled by instruction cards, and later were fed as a string of connected cards.
This lead to the concept of communicating analog data not as a stream of individual cards, but one "continuous card", or a tape. Many professional embroidery operations still refer to those individuals who create the designs and machine patterns as "punchers", even though punched cards, and paper tape, was eventually phased out, after many years of use, in the 1990s.
Punched tape was eventually also used as a way of storing messages for teletypewriters. The idea was to type in the message to the paper tape, and then send the message at "high speed" from the tape. The tape reader could "type" the message faster than a typical human operator, thus saving on phone bills.
When the first computers were being released many turned to the teletypewriter as a low-cost solution for printer output. This is why computers today still use ASCII, which was intended to be the standard character set for operating teletypewriters. As a side effect the punched tape readers became a popular medium for low cost storage, and it was common to find a selection of tapes containing useful program in most computer installations.
The little pieces of paper punched out of the tape are known as chad.
See also: punch card, chadless tape
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