The IEEE Spectrum has a lovely article about the origins and early history of PostScript and how it jumpstarted desktop publishing and arguably digital printing. Most Irreal readers probably know the rudiments of the story. PostScript was developed at Adobe Systems for electronic printing and rapidly became the standard for digital printers.
The actual story is more complicated. Previous digital printing technology involved producing handcrafted bitmapped images of each character in each font of each typeface. Adobe’s plan was to describe each character of a typeface mathematically (using Bézier curves) and scale (or even rotate) the descriptions mathematically for each font.
One of the hardest problems was dealing with the different resolutions of various printers. The 300 DPI resolution of the early laser printers were from different from the, say, 1200 DPI of commercial printers. The fix involves flipping bits at the critical points of a character where the jaggedness appears at lower resolutions. This was accomplished by means of “hints” for each character and associated procedures for each resolution.
One of the interesting parts of the article was a video of Chuck Geschke talking about how Adobe came to focus on PostScript. The original plan, as I understand it, was to produce computer driven printing presses. Early on, both DEC and Apple approached Adobe and said essentially the same thing: “We already from computers and have a deal with a printer manufacturer for a printer but we’re having trouble getting the computer to talk to the printer. Sell us your software.” In both cases Adobe demurred, citing its business plan and its obligations under it. Later one of their investors said that DEC and APPLE had been right and that they should focus on the software that later became PostScript.
It’s a really interesting article and well worth a few minutes of your time. These days, of course, PostScript has pretty much taken over digital printing and it’s worth taking a look at how it all began.