PostScript:: n. A Page Description Language ({PDL})

:PostScript:: n. A Page Description Language ({PDL}), based on
work originally done by John Gaffney at Evans and Sutherland in
1976, evolving through `JaM' (`John and Martin', Martin Newell) at
{XEROX PARC}, and finally implemented in its current form by
John Warnock et al. after he and Chuck Geschke founded Adobe
Systems Incorporated in 1982. PostScript gets its leverage by
using a full programming language, rather than a series of
low-level escape sequences, to describe an image to be printed on a
laser printer or other output device (in this it parallels
{EMACS}, which exploited a similar insight about editing
tasks). It is also noteworthy for implementing on-the fly
rasterization, from Bezier curve descriptions, of high-quality
fonts at low (e.g. 300 dpi) resolution (it was formerly believed
that hand-tuned bitmap fonts were required for this task). Hackers
consider PostScript to be among the most elegant hacks of all time,
and the combination of technical merits and widespread availability
has made PostScript the language of choice for graphical
output.
-- The AI Hackers Dictionary