The Info List - Paper Data Storage

data storage refers to the use of paper as a data storage device. This includes writing, illustrating, and the use of data that can be interpreted by a machine or is the result of the functioning of a machine. A defining feature of paper data storage is the ability of humans to produce it with only simple tools and interpret it visually. Though this is now mostly obsolete, paper was once also an important form of computer data storage.


1 History 2 Limits 3 See also 4 References 5 External links

History[edit] Before paper was used for storing data, it had been used in several applications for storing instructions to specify a machine's operation. The earliest use of paper to store instructions for a machine was the work of Basile Bouchon
Basile Bouchon
who, in 1725, used punched paper rolls to control textile looms. This technology was later developed into the wildly successful Jacquard loom. The 19th century saw several other uses of paper for controlling machines. In 1846, telegrams could be prerecorded on punched tape and rapidly transmitted using Alexander Bain's automatic telegraph. Several inventors took the concept of a mechanical organ and used paper to represent the music. In the late 1880s Herman Hollerith
Herman Hollerith
invented the recording of data on a medium that could then be read by a machine. Prior uses of machine readable media, above, had been for control (automatons, piano rolls, looms, ...), not data. "After some initial trials with paper tape, he settled on punched cards..."[1] Hollerith's method was used in the 1890 census. Hollerith's company eventually became the core of IBM. Other technologies were also developed that allowed machines to work with marks on paper instead of punched holes. This technology was widely used for tabulating votes and grading standardized tests. Barcodes made it possible for any object that was to be sold or transported to have some computer readable information securely attached to it. Banks used magnetic ink on checks, supporting MICR scanning. In an early electronic computing device, the Atanasoff-Berry Computer, electric sparks were used to singe small holes in paper cards to represent binary data. The altered dielectric constant of the paper at the location of the holes could then be used to read the binary data back into the machine by means of electric sparks of lower voltage than the sparks used to create the holes. This form of paper data storage was never made reliable and was not used in any subsequent machine. As of 2014, Universal Product Code
Universal Product Code
barcodes, first used in 1974, are ubiquitous. Some people recommend a width of at least 3 pixels for each minimum-width gap and each minimum-width bar for 1D barcodes; and a width of at least 4 pixels—e.g., a 4 × 4 pixel = 16 pixel module for 2D barcodes.[2] For a typical black-and-white barcode scanned by a typical 300 dpi image scanner, and assuming roughly half the space is occupied by finder patterns, fiducial alignment patterns, and error detection and correction codes, that recommendation gives a maximum data density of roughly 50 bits per linear inch (about 2 bit/mm) for 1D barcodes, and roughly 2 800 bits per square inch (about 4.4 bit/mm2). Limits[edit] The limits of data storage depend on the technology to write and read such data. For example, an 8″ × 10″ (roughly A4 without margins) 300dpi 8-bit greyscale image map contains 7.2 megabytes of data—assuming a scanner can accurately reproduce the printed image to that resolution and color depth, and a program can accurately interpret such an image. A similarly sized image in 2400dpi 24-bit true color theoretically contains 1.38 gigabytes of information. See also[edit]

read by a vending machine Book music Edge-notched card Index card Kimball tag Machine-readable medium Magnetic ink character recognition Mark sense Music roll Optical mark recognition Paper
disc Perfin Perforation Punched tape Spindle (stationery) Stenotype Ticker tape


^ Columbia University Computing History - Herman Hollerith ^ Accusoft. "Using Barcodes in Documents – Best Practices". 2007. Retrieved 2014-04-25.

External links[edit]

DataGlyphs PaperBack data storage

v t e

data storage media


on papyrus (c. 3000 BCE) Paper
(105 CE)


Index card
Index card
(1640s) Punched tape
Punched tape
(mid-1800s) Punched card
Punched card
(1880s) Edge-notched card
Edge-notched card
(1896) Optical mark recognition
Optical mark recognition
(1930s) Optical character recognition (1950s) Ba