How PostScript Kickstarted Desktop Publishing

The story of PostScript has many various sides. It is a narrative about profound adjustments in human literacy in addition to a narrative of commerce secrets and techniques inside supply code. It is a narrative in regards to the significance of groups and of geometry. And it’s a story of the motivations and educations of engineer-entrepreneurs.

The Computer History Museum is happy to publicly launch, for the primary time, the supply code for the breakthrough printing expertise, PostScript. (Register to obtain the code right here.) We thank Adobe for the corporate’s permission and help, and Adobe cofounder John Warnock for championing this launch.

The Big Picture of Printing

Printing has all the time been a expertise with profound cultural penalties. Movable sort first emerged in East Asia. Later, in Fifteenth-century Europe, the printing press developed from expertise from wine and oil presses mixed with novel practices to mass-produce sort utilizing steel casting. With the printing press got here a revolution in human literacy. Books turned cheaper and faster to supply, and in consequence appeared in ever higher numbers. Literacy and libraries expanded. Greater entry to info remodeled studying, analysis, authorities, commerce, and the humanities.

John Warnock [left] and Chuck Geschke based Adobe Systems in December 1982.Adobe and Doug Menuez

From the beginning of Adobe Systems (now Adobe) 40 years in the past, in December 1982, the agency’s cofounders envisioned a brand new form of printing press—one which was essentially digital, utilizing the most recent advances in computing. Initial discussions by cofounders Chuck Geschke and John Warnock with pc makers akin to Digital Equipment Corp. and Apple satisfied them that software program was the important thing to the brand new digital printing press. Their imaginative and prescient: Any pc might join with printers and typesetters by way of a typical language to print phrases and pictures on the highest constancy. Led by Warnock, Adobe assembled a crew of skillful and inventive programmers to create this new language. In addition to the 2 cofounders, the crew included Doug Brotz, Bill Paxton, and Ed Taft. The language they created was a whole programming language, named PostScript, and was launched by Adobe in 1984.

In this video, Geschke discusses how Adobe got here to deal with PostScript:

Chuck Geschke discusses how Adobe got here to deal with PostScript as their preliminary enterpriseComputer History Museum

By treating all the things to be printed the identical, in a typical mathematical description, PostScript granted skills provided nowhere else. Text and pictures might be scaled, rotated, and moved at will, as within the opening picture to this essay. Adobe licensed PostScript to pc and printer producers, and the enterprise jumped right into a interval of hypergrowth. There was large demand for the brand new software program printing press. Computer makers from the established worlds of minicomputers and workstations to the quickly rising world of non-public computer systems adopted the expertise. Printer makers joined in, from these promoting well-established printers to the brand new laser printers {and professional} typesetters. Software makers rushed to make their choices suitable with PostScript.

Fueling this progress have been advances Adobe was making round a crucial want: offering professional-quality digital typefaces—and the various fonts that comprise them—to be used inside PostScript. Adobe developed a recent strategy to describing typefaces geometrically, and the corporate licensed most of the most well-known typefaces, together with these for Asian languages. PostScript and the Adobe Type Library revolutionized printing and publishing, and kickstarted the explosive progress of desktop publishing beginning within the Eighties. PostScript turned so profitable that it grew right into a de facto normal internationally, with Adobe publishing the main points of the PostScript language and permitting others to create merchandise that have been PostScript-compatible. Today, most printers depend on PostScript expertise both straight or by way of a expertise that grew out of it: PDF, or Portable Document Format.

Trajan was an early typeface created by Adobe utilizing its new applied sciences.Adobe

Warnock championed the event of PDF within the Nineties, remodeling PostScript right into a expertise that was safer and simpler to make use of for digital paperwork, however retaining all the advantages of interoperability, constancy, and high quality. Over the a long time, Adobe continued to boost PDF’s options, making it an important normal for creating digital paperwork, printing them, and displaying graphics of all types on screens from desktops to laptops to smartphones and smartwatches.

Today, the digital printing press has far exceeded something envisioned by the Adobe cofounders after they first got down to create PostScript with their crew. Almost all the things printed on paper is finished so utilizing computer systems. Indeed, in lots of areas of the world, computer systems have grow to be the overwhelming instrument for writing. As Doug Brotz places it, PostScript “democratized the print world.” With PDF now so profitable that it too has grow to be a world normal, the variety of PDFs created annually measures within the trillions.

PostScript’s Graphical Roots

Typography is the mix of artwork and approach that’s involved with the show of writing, particularly as printed. It is anxious with the form and placement of characters, phrases, paragraphs, and so forth. In this, typography is totally graphical, a matter of visible design. Digital typography isn’t any completely different, simply centered to pc strategies and shows. It is becoming, then, that the roots of PostScript and its contributions to the event of digital typography lie in superior pc graphics.

Warnock, the architect for PostScript, launched his computing profession as a graduate scholar on the University of Utah on the shut of the Sixties. Utah was then one of many world’s foremost facilities for superior pc graphics analysis. In his work there after which at a pc graphics agency run by Utah’s lead professors, David Evans and Ivan Sutherland, Warnock embraced their attribute geometric strategy to pc graphics. Shapes, scenes, photos, and animations have been created and designed utilizing arithmetic to explain the geometry of the visible and utilizing varied pc procedures to appreciate these descriptions as imagery. In specific, Warnock was impressed with the ability of a procedural pc language, known as the Design System, that he and John Gaffney helped to develop at Evans and Sutherland’s agency.

In 1978, Chuck Geschke had simply arrange the Imaging Science Laboratory inside the famed Xerox Palo Alto Research Center (PARC). Geschke employed Warnock to take up a urgent problem for the lab. PARC was making a set of experimental computer systems that had new sorts of shows and that have been meant for use with an array of novel printers—as PARC had lately invented the laser printer. Warnock’s problem was to create a device-independent graphics system that might be used throughout any pc, show, or printer.

Warnock noticed that one thing just like the Design System might work on this new computing setting, however refocused from 3D graphics to PARC’s concern with professional-quality printing and high-quality show of textual content and pictures. The outcome was one other geometrical, procedural language known as JaM, which Warnock created in partnership with PARC researcher Martin Newell. (The illustration at prime was created utilizing JaM.)

From 1979 into 1981, JaM turned a serious part in a brand new effort in Geschke’s laboratory. This was a push to develop a industrial printing language that might be used with the manufacturing model of PARC’s experimental computer systems known as the Xerox Star, and extra broadly used throughout all of Xerox’s traces of printers. A gaggle of six researchers—Geschke, Butler Lampson, Jerry Mendelson, Brian Reid, Bob Sproull, and Warnock—melded the JaM strategy with different, extra established protocol strategies. The outcome was named Interpress.

Xerox management was rapidly satisfied of the potential for Interpress, deciding that it will certainly be developed into the agency’s printing normal. However, transferring to this normal would take a number of years, throughout which era Interpress could be below wraps. This delay spurred Geschke and Warnock to maneuver. They would go away PARC and located a startup through which they’d create a rival to Interpress, however constructed extra absolutely alongside the geometric, procedural language strategy that Warnock discovered to be so highly effective. For the brand new startup to create this new language, PostScript, because the digital printing press, it will require a superb crew.

In this video clip, Geschke discusses the motivations behind the formation of Adobe:

Chuck Geschke discusses the motivations behind the formation of AdobeComputer History Museum

In this video clip, Warnock discusses key early actions in establishing Adobe.

John Warnock discusses key early actions in establishing AdobeComputer History Museum

The Team that Created PostScript

In December 1982, when Geschke and Warnock based Adobe Systems, the brand new printing language they meant to create was on the very heart of their plans, hopes, and imaginative and prescient. The way forward for the agency hinged on PostScript. Geschke and Warnock have been themselves each extremely skilled software program creators. Geschke had earned his Ph.D. at Carnegie Mellon University engaged on superior compilers and had been a pacesetter within the creation of an necessary programming language developed and used at PARC known as Mesa. As mentioned, Warnock had a Ph.D. in pc graphics software program from the University of Utah and years of expertise creating languages precisely like their envisioned PostScript. But maybe due to their intensive background in creating cutting-edge software program, the cofounders knew they wanted to broaden their crew to create PostScript.

Early Adobe staff and mates sail within the San Francisco Bay on an organization outing.Adobe

Adobe’s PostScript crew rapidly took form as three different extremely gifted software program creators from PARC determined to hitch with Geschke and Warnock: Doug Brotz, Bill Paxton, and Ed Taft. Brotz had earned a Ph.D. in pc science from Stanford earlier than becoming a member of PARC in 1977. Paxton additionally had a Ph.D. in pc science from Stanford and joined PARC the identical 12 months as Brotz. Taft had joined PARC earlier, employed by Geschke proper after ending his undergraduate research at Harvard in 1973. Together, and with enter from Adobe colleagues like Andy Shore, the crew created PostScript by the shut of 1984.

A Trade Secret within the Source Code

Adobe’s dedication to a geometrical strategy for PostScript carried penalties for the way it will take care of typefaces—distinctive character shapes—and the quite a few fonts that really understand these typefaces at completely different sizes and kinds (level sizes, common, italic, daring, and so forth). At PARC, fonts had been created as a set of particular person hand-crafted bitmap photos, with static definitions of which bits have been on and which have been off for every character of the font. Meanwhile, although, researchers at PARC and past have been exploring methods to outline character shapes mathematically. At Adobe, the crew adopted this mathematical description strategy to fonts, consistent with the broader path of PostScript, defining characters utilizing Bézier curves.

But this nonetheless left the issue of device-independence. How might Adobe’s font definitions take care of completely different shows, printers, and completely different resolutions on each? For eyes accustomed to studying revealed textual content, even the slightest inconsistencies or irregularities within the look of textual content are readily seen and jarring. At decrease resolutions, the prospect for these defects solely turns into worse. Rendering fonts reliably at completely different resolutions was a crucial situation. Without an answer, PostScript might by no means grow to be the digital printing press.

Elements of Adobe’s secret answer to creating professional-quality fonts for various resolutions on shows and printers.John Warnock

It was Warnock who got here up with Adobe’s answer, turning the issue itself into the answer. The decision of the output would decide a set of procedures that will appropriate the fonts to optimize their look at that decision. Warnock, Brotz, and Paxton labored on the procedures for months, finally deciding on methods to outline key points of the font shapes and becoming them to the pixel rows and columns of the desired decision, altering some points of the character shapes relying on the decision. Eventually, the Adobe crew determined that best benefit lay in conserving these approaches and procedures as a commerce secret. They stayed secret in PostScript’s supply code, identified to only a few on the firm, till Warnock publicly disclosed them in a 2010 lecture. In this video clip, Geschke discusses the commerce secret within the PostScript supply code:

Chuck Geschke discusses the commerce secret within the PostScript supply codeComputer History Museum

The model of the PostScript supply code launched to the general public by the Computer History Museum is a really early model, relationship to late February 1984. While this model does include an early model of the “font hinting” procedures later stored as a commerce secret, these approaches have been fully rewritten, expanded, and refined by Bill Paxton in subsequent months. These adjustments have been crucial to the success of PostScript because it absolutely got here to market.

Editor’s word: This submit initially appeared on the weblog of the Computer History Museum.

Acknowledgements: Thank you to Doug Brotz and Bill Paxton for his or her useful feedback on a draft of this essay. Thank you to Adobe and Doug Menuez for permission to make use of a number of photos.

This essay is predicated on oral histories and interviews carried out by the Computer History Museum in addition to a number of crucial revealed sources:

John E. Warnock, “The Origins of PostScript,” in IEEE Annals of the History of Computing, vol. 40, no. 3, pp. 68-76, Jul.-Sep. 2018, doi: 10.1109/MAHC.2018.033841112.

John E. Warnock, “Simple Ideas That Changed Printing and Publishing,” in Proceedings of the American Philosophical Society, vol. 156, no. 4, 2012, pp. 363–78. JSTOR, http://www.jstor.org/stable/23558230.

John E. Warnock and Charles Geschke, “Founding and Growing Adobe Systems, Inc.,” in IEEE Annals of the History of Computing, vol. 41, no. 3, pp. 24-34, July-Sept. 2019, doi: 10.1109/MAHC.2019.2923397.