
\S request:  macro:  register:  macro package \S

Requests, registers, and macros are all used as instructions for formatting
text using the text processors troff(1) and nroff(1).  When a text
processing program encounters one of these in your file, it interprets it
and formats your file accordingly.

Requests are instructions that are predefined by your text processing
program.  A request effects the text that immediately follows it. You can
intersperse text and requests throughout the document.  Requests are
usually represented as two lower case letters that are alone on a line.

Macros are used to represent many requests that you use often.  They keep
you from typing many requests over and over again.  When you execute the
text processing programs nroff(1) or troff(1), the macros are replaced by
the requests they represent.  Macros are usually one or two upper case
letters that appear alone on a line.

Macro packages further simplify the job of formatting text.  These packages
have macros to create headers, titles, footnotes and various other jobs
that complicate text formatting.  nroff(1) offers three macro packages:  mm
to format memorandums; man for formatting manual pages; and mptx for
formatting permuted indices.  To use these packages, you include the name
of the macro package as an option on the nroff(1) command line.

Registers are used to define formatting for sections of your document.
Each register controls a different attribute of the text such as the size
and type of message in the footer, the spacing for paragraphs, and
indenting of paragraphs.  You include the register name plus an integer on
the nroff(1) command line.  The integer dictates which of the choices for
the register you would like to use.  The attribute that the register
controls will be handled the same way throughout the document.  Registers
are typically an upper case letter followed by a lower case letter.  See
the "Documenter's Workbench Software Technical Discussion and Reference
Manual" for details on text formatting.
