@Section
    @Title { Introduction }
@Begin
@PP
Lout [1, 2] is a high-level language
for document formatting, designed and implemented by the author.  The
implementation, known as Basser Lout, is a fully operational production
version written in C for the Unix operating system,
@FootNote { Unix is a trademark of "AT&T" Bell Laboratories. }
which translates Lout source code into PostScript,
@FootNote { PostScript is a trademark of Adobe Systems, Incorporated. }
a device-independent graphics rendering language accepted by many
high-resolution output devices, including most laser printers.  Basser
Lout is available free of charge [3].  It includes
installation instructions, C source, seven standard packages, and complete
documentation in the form of six technical reports and a manual page.
@PP
The Lout project arose out of the author's desire to bring to document
formatting languages the elegance of expression found in programming
languages like Algol-60 and Pascal.  This emphasis on expressiveness
has produced an order of magnitude reduction in the cost of developing
document formatting applications.  For example, an equation formatting
application, which may be difficult or impossible to add to other
systems, can be written in Lout in a few days.
@PP
When expert users can implement such applications quickly, non-experts
benefit.  Although Lout itself provides only a small kernel of carefully
chosen primitives, packages written in Lout and distributed with Basser
Lout provide an unprecedented array of advanced features in a form
accessible to non-expert users.  The features include rotation and scaling,
fonts, paragraph and page breaking, displays and lists, floating figures
and tables, footnotes, chapters and sections (automatically numbered),
running page headers and footers, odd-even page layouts, automatically
generated tables of contents, sorted indexes and reference lists,
bibliographic and other databases (including databases of formats for
printing references), equations, tables, diagrams, formatting of
Pascal programs, and automatically maintained cross references.
@PP
This paper charts the evolution of Lout from conception in mid-1984 to the
public release of Basser Lout in October 1991.  Lout is organized around
four key concepts -- objects, definitions, galleys, and cross references --
and they were developed in the order listed, so this paper will treat each
in turn, discussing its design, implementation, problems, and
prospects for further improvement.
@End @Section