paper tape

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paper tape An obsolete but once widely used data medium in the form of a continuous tape of paper with uniform width and thickness and specified physical attributes; other materials included laminates of paper and polyester. Data was encoded by punching patterns of holes on the tape. Generally a data character was punched as a coded set of holes across the tape at standard pitch. One-inch wide tape could accommodate characters of up to 8 bits. In addition to the data tracks running along the length of the tape, a full track of smaller-diameter sprocket or feed holes became an essential feature for synchronization. The data and feed holes were later sensed optically, thus the optical characteristics of the material became part of the specification. The tape was normally wound onto a core of standardized dimensions.

Punched paper tape was in use for data communication purposes (telex) prior to its use for computer input/output. It has also been used for programmed control of industrial equipment, and the preprogrammed control of continuous paper through computer printers.