The GSI C/A/T (Computer Assisted Typesetter) is a

phototypesetter Phototypesetting is a method of setting type. It uses photography to make columns of type on a scroll of photographic paper. It has been made obsolete by the popularity of the personal computer and desktop publishing (digital typesetting). The ...

developed by Graphic Systems in 1972. This phototypesetter, along with

troff troff (), short for "typesetter roff", is the major component of a document processing system developed by Bell Labs for the Unix operating system. troff and the related nroff were both developed from the original roff. While nroff was inten ...

software for

UNIX Unix (; trademarked as UNIX) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, and ot ...

, revolutionized the

typesetting Typesetting is the composition of text by means of arranging physical ''type'' (or ''sort'') in mechanical systems or ''glyphs'' in digital systems representing ''characters'' (letters and other symbols).Dictionary.com Unabridged. Random Ho ...

and document

printing Printing is a process for mass reproducing text and images using a master form or template. The earliest non-paper products involving printing include cylinder seals and objects such as the Cyrus Cylinder and the Cylinders of Nabonidus. The ea ...

industry. Phototypesetting is most often used with

offset printing Offset printing is a common printing technique in which the inked image is transferred (or "offset") from a plate to a rubber blanket and then to the printing surface. When used in combination with the lithographic process, which is based on t ...

technology. The GSI C/A/T phototypesetter was marketed by

Singer Corporation Singer Corporation is an American manufacturer of consumer sewing machines, first established as I. M. Singer & Co. in 1851 by Isaac M. Singer with New York lawyer Edward C. Clark. Best known for its sewing machines, it was renamed Singer Ma ...

in 1974 before the company was purchased by

Wang Laboratories Wang Laboratories was a US computer company founded in 1951 by An Wang and G. Y. Chu. The company was successively headquartered in Cambridge, Massachusetts (1954–1963), Tewksbury, Massachusetts (1963–1976), and finally in Lowell, Massachusett ...

in 1978. Graphic Systems designed a simple computer front end to print basic text as display type. Full-scale page-composition computing was designed at

Bell Laboratories Nokia Bell Labs, originally named Bell Telephone Laboratories (1925–1984), then AT&T Bell Laboratories (1984–1996) and Bell Labs Innovations (1996–2007), is an American industrial research and scientific development company owned by mult ...

as part of the UNIX project.

Features

The C/A/T phototypesetter features: * Punched paper tape for document input * Four font film strips with 102 characters or

glyph A glyph () is any kind of purposeful mark. In typography, a glyph is "the specific shape, design, or representation of a character". It is a particular graphical representation, in a particular typeface, of an element of written language. A g ...

s per strip * Canisters of photographic paper or film to receive the image * Fifteen distinct font sizes (5 pt to 72pt) * Horizontal positioning precision of 432 units per inch * Vertical positioning precision of 144 units per inch C/A/T optics consist of a rotating wheel to which are attached film strips of master font characters. The wheel's periphery has four such replaceable font film strip sections. A

xenon Xenon is a chemical element with the symbol Xe and atomic number 54. It is a dense, colorless, odorless noble gas found in Earth's atmosphere in trace amounts. Although generally unreactive, it can undergo a few chemical reactions such as the ...

strobe A strobe light or stroboscopic lamp, commonly called a strobe, is a device used to produce regular flashes of light. It is one of a number of devices that can be used as a stroboscope. The word originated from the Ancient Greek ('), meaning ...

inside the wheel is programmed to flash the characters from the font films through magnification optics to a

fiber-optic An optical fiber, or optical fibre in Commonwealth English, is a flexible, transparent fiber made by drawing glass (silica) or plastic to a diameter slightly thicker than that of a human hair. Optical fibers are used most often as a means t ...

bundle. The programmable location of the fiber-optic bundle determines the horizontal position of the character image on a scroll of photographic paper or film. C/A/T is a highly addressable phototypesetter with full optics control from computer-generated data. This precise control of optics and image position made the interface to computer programs reasonably simple. Data is normally transmitted to the C/A/T by paper tape. Some companies created electronic replacements for the paper-tape interface to accommodate direct connection to computer systems. C/A/T has no page layout and pagination capability. It is only a high-resolution printer that puts high-resolution character images onto a photographic medium. Page layout is determined by the

software used to generate the paper tape.

Timeline

* 1971, Graphic Systems designs and markets the C/A/T phototypesetter. * 1972, Graphic Systems provides a simple computer front end to handle display typesetting from text input using a standard set of fonts. * 1973, Bell Laboratories purchases a GSI C/A/T phototypesetter for their UNIX software development team. * 1973, The troff software was created by Joe F. Ossanna at Bell Labs. * 1974, Graphic Systems partners with Singer Corporation to market the GSI C/A/T phototypesetter. Singer Corporation was allowed to put the Singer C/A/T logo on equipment they sold. * 1978, Singer Corporation gets out of the typesetting business. * 1978, Wang Laboratories purchases Graphic Systems and continues to market the GSI C/A/T typesetter for UNIX-based phototypesetting. The phototypesetter was then known as the Wang Graphic Systems C/A/T. This allowed the phototypesetter to be available through the 1980s. * 1979,

ditroff troff (), short for "typesetter roff", is the major component of a document processing system developed by Bell Labs for the Unix operating system. troff and the related nroff were both developed from the original roff. While nroff was inten ...

software was created by

Brian Kernighan Brian Wilson Kernighan (; born 1942) is a Canadian computer scientist. He worked at Bell Labs and contributed to the development of Unix alongside Unix creators Ken Thompson and Dennis Ritchie. Kernighan's name became widely known through co-au ...

. * 1979,

TeX Tex may refer to: People and fictional characters * Tex (nickname), a list of people and fictional characters with the nickname * Joe Tex (1933–1982), stage name of American soul singer Joseph Arrington Jr. Entertainment * ''Tex'', the Italian ...

software was created by

Donald E. Knuth Donald Ervin Knuth ( ; born January 10, 1938) is an American computer scientist, mathematician, and professor emeritus at Stanford University. He is the 1974 recipient of the ACM Turing Award, informally considered the Nobel Prize of computer sc ...

. * 1981–1983,

LaTeX Latex is an emulsion (stable dispersion) of polymer microparticles in water. Latexes are found in nature, but synthetic latexes are common as well. In nature, latex is found as a milky fluid found in 10% of all flowering plants (angiosperms ...

software was created by

Leslie Lamport Leslie B. Lamport (born February 7, 1941 in Brooklyn) is an American computer scientist and mathematician. Lamport is best known for his seminal work in distributed systems, and as the initial developer of the document preparation system LaTeX and ...

. * 1992, Wang Laboratories declared

Chapter 11 bankruptcy Chapter 11 of the United States Bankruptcy Code (Title 11 of the United States Code) permits reorganization under the bankruptcy laws of the United States. Such reorganization, known as Chapter 11 bankruptcy, is available to every business, whe ...

History

Bell Labs purchased a C/A/T phototypesetter in 1973 for their engineers who were developing the UNIX operating system. C/A/T became the

de facto standard A ''de facto'' standard is a custom or convention that has achieved a dominant position by public acceptance or market forces (for example, by early entrance to the market). is a Latin phrase (literally " in fact"), here meaning "in practice b ...

for UNIX-based typesetting. The early typesetting programs on general-purpose computers displaced special-purpose photocomposition systems. Noteworthy typesetting software created for C/A/T includes troff (1973), which was developed by Joe F. Ossanna at Bell Labs. Brian Kernighan later developed

(typesetter independent troff), which supported the C/A/T and other publishing systems. C/A/T was the workhorse of UNIX printing through the 1980s for shops that could not afford hot lead typography equipment or expensive and proprietary document typesetting systems. High-resolution

laser printing Laser printing is an electrostatic digital printing process. It produces high-quality text and graphics (and moderate-quality photographs) by repeatedly passing a laser beam back and forth over a negatively-charged cylinder called a "drum" to d ...

, now common in desktop publishing, was not yet available. Graphic Systems did not have the marketing capability to dominate the phototypesetting business. Singer Manufacturing Company around 1975 acquired the rights to market the hardware, including placing the Singer C/A/T logo on the products. Singer continued to support C/A/T systems until 1979. Wang Laboratories bought Graphic Systems in 1978. The phototypesetter was then known as Wang Graphic Systems C/A/T with continued support through the 1980s. Advances in electronic typesetting programs such as ditroff (1979),

(1979), and

(1981–1983) obsoleted the C/A/T phototypesetter. C/A/T continued to be prevalent in many UNIX-based documentation shops until high-quality laser printers became prevalent.

Singer Corporation Typesetting

Standard error

The output stream

standard error The standard error (SE) of a statistic (usually an estimate of a parameter) is the standard deviation of its sampling distribution or an estimate of that standard deviation. If the statistic is the sample mean, it is called the standard error ...

(stderr), a standard on many systems for over 40 years, was first created because of this device. Initially, error messages from typesetting software were also sent to the typesetter, wasting time and materials. This prompted the creation of a separate output channel for error messages.

References

{{Reflist Typesetting Products introduced in 1972 Discontinued products