postscript
     n 1: a note appended to a letter after the signature [syn: {PS}]
     2: textual matter that is added onto a publication; usually at
        the end [syn: {addendum}, {supplement}]
Source: WordNet® 2.0

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.


Source: The Jargon File