Interpress and PostScript enabled display technology, initially printers and eventually screens, to display output exactly as it would look between media. Printouts and screens, no matter the size, would look exactly the same. The technology is another from Xerox PARC.
Background
Warnock left Evans & Sutherland, a computer graphics company founded by Ivan Sutherland, to join Xerox PARC. His was a page description language for laser printers. There was a prior page description language, “Press,” but it was inadequate.
At Xerox PARC, Warnock created Interpress to describe printed material.
Xerox executives repeatedly refused to meaningfully commit to commercializing the technology. Eventually, in 1982, Warnock and his boss Chuck Geschke, quit. They formed a new company, Adobe, to create a programming language for page descriptions, PostScript. They wrote the entire language from scratch.
Before PostScript, every printer had a proprietary means of communication. This made programming output especially difficult.
Jobs Adopts PostScript
Steve Jobs liked PostScript and invested $2.5 million for Adobe to finish the technology. He adopted it for use in Apple’s personal laser printer, the LaserWriter.
PostScript eventually caught on for printers and spawned a similar general-purpose page description language for screens. That technology is branded the Portable Document Format, or PDF, and remains widely in use today.
Eventually, Jobs used a modified version of PDF at Next Computer, the company he founded after Apple fired him. When Apple rehired him, Jobs incorporated screen PDF into the Macintosh. To this day, pieces and parts of PDF exist in both the Macintosh and iOS operating systems.
To gain wide adoption, Adobe eventually open-sourced PDF.
Today, Adobe does no substantive ongoing work on PostScript but remains a large company thanks to other innovations it fostered, especially software for graphic artists. Warnock eventually retired a multibillionaire but Xerox made no money from his work.