|n.||1.||A paragraph added to a letter after it is concluded and signed by the writer; an addition made to a book or composition after the main body of the work has been finished, containing something omitted, or something new occurring to the writer.|
|Noun||1.||postscript - a note appended to a letter after the signature|
|2.||postscript - textual matter that is added onto a publication; usually at the end|
|(language, text, graphics)||PostScript - A page description language 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, Inc. in 1982.|
PostScript is an interpreted, stack-based language (like FORTH). It was used as a page description language by the Apple LaserWriter, and now many laser printers and on-screen graphics systems. Its primary application is to describe the appearance of text, graphical shapes, and sampled images on printed or displayed pages.
A program in PostScript can communicate a document description from a composition system to a printing system in a device-independent way.
PostScript is an unusually powerful printer language because it is a full programming language, rather than a series of low-level escape sequences. (In this it parallels Emacs, which exploited a similar insight about editing tasks). It is also noteworthy for implementing on-the fly rasterisation, 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).
PostScript's combination of technical merits and widespread availability made it the language of choice for graphical output until PDF appeared.
The Postscript point, 1/72 inch, is slightly different from other point units.
["PostScript Language Reference Manual" ("The Red Book"), Adobe Systems, A-W 1985].