PostScript
Adobe's page description language from 1984, created by John Warnock and Chuck Geschke. A full stack-based programming language — the page you print is the result of a program running inside the printer.
The syntax is postfix in the Forth tradition: 100 200 moveto followed by (Hello) show. Turing complete, meaning a PostScript file need never terminate — hence the print queues that hung forever in the 1980s. Apple LaserWriter plus PostScript plus PageMaker kicked off the desktop publishing revolution in 1985. PDF is essentially PostScript with the programmability removed: same graphics model, but declarative and page-independent, so page 400 can be rendered without executing pages 1–399 first.