groff(1)


NAME

   groff - front-end for the groff document formatting system

SYNOPSIS

   groff [-abcegijklpstzCEGNRSUVXZ] [-d cs] [-D arg] [-f fam] [-F dir]
         [-I dir] [-K arg] [-L arg] [-m name] [-M dir] [-n num] [-o list]
         [-P arg] [-r cn] [-T dev] [-w name] [-W name] [file ...]
   groff -h | --help
   groff -v | --version [option ...]

DESCRIPTION

   This  document  describes the groff program, the main front-end for the
   groff document formatting system.  The groff program and macro suite is
   the  implementation  of  a  roff(7)  system  within  the  free software
   collection GNU http://www.gnu.org.  The groff system has all features
   of the classical roff, but adds many extensions.

   The  groff  program allows to control the whole groff system by command
   line options.  This is a great  simplification  in  comparison  to  the
   classical case (which uses pipes only).

OPTIONS

   The  command line is parsed according to the usual GNU convention.  The
   whitespace between a command line option and its argument is  optional.
   Options  can  be  grouped  behind  a  single  '-' (minus character).  A
   filename of - (minus character) denotes the standard input.

   As groff is a wrapper program for troff both programs share  a  set  of
   options.  But the groff program has some additional, native options and
   gives a new meaning to some troff options.  On the other hand, not  all
   troff options can be fed into groff.

   Native groff Options
   The  following options either do not exist for troff or are differently
   interpreted by groff.

   -D arg Set default input encoding used by preconv to arg.  Implies -k.

   -e     Preprocess with eqn.

   -g     Preprocess with grn.

   -G     Preprocess with grap.  Implies -p.

   -h
   --help Print a help message.

   -I dir This option may be used to specify a  directory  to  search  for
          files  (both  those on the command line and those named in .psbb
          and .so requests, and \X'ps: import' and \X'ps: file'  escapes).
          The current directory is always searched first.  This option may
          be specified more than once; the directories are searched in the
          order  specified.   No  directory  search is performed for files
          specified using an absolute path.  This option  implies  the  -s
          option.

   -j     Preprocess with chem.  Implies -p.

   -k     Preprocess   with   preconv.   This  is  run  before  any  other
          preprocessor.  Please refer to preconv's  manual  page  for  its
          behaviour if no -K (or -D) option is specified.

   -K arg Set input encoding used by preconv to arg.  Implies -k.

   -l     Send  the output to a spooler program for printing.  The command
          that should be used for this is specified by the  print  command
          in  the  device  description  file,  see groff_font(5).  If this
          command is not present, the output  is  piped  into  the  lpr(1)
          program by default.  See options -L and -X.

   -L arg Pass  arg  to  the spooler program.  Several arguments should be
          passed with a separate -L option each.  Note that groff does not
          prepend  '-'  (a  minus  sign)  to  arg before passing it to the
          spooler program.

   -N     Don't allow newlines within eqn delimiters.  This is the same as
          the -N option in eqn.

   -p     Preprocess with pic.

   -P -option
   -P -option -P arg
          Pass  -option  or  -option arg to the postprocessor.  The option
          must be specified with the necessary preceding minus sign(s) '-'
          or '--' because groff does not prepend any dashes before passing
          it to the postprocessor.  For example, to pass a  title  to  the
          gxditview postprocessor, the shell command

                 groff -X -P -title -P 'groff it' foo

          is equivalent to

                 groff -X -Z foo | gxditview -title 'groff it' -

   -R     Preprocess  with  refer.   No  mechanism is provided for passing
          arguments to refer because most refer  options  have  equivalent
          language  elements  that  can  be specified within the document.
          See refer(1) for more details.

   -s     Preprocess with soelim.

   -S     Safer mode.  Pass the -S option to pic and disable the following
          troff requests: .open, .opena, .pso, .sy, and .pi.  For security
          reasons, safer mode is enabled by default.

   -t     Preprocess with tbl.

   -T dev Set output device to dev.  For this device, troff generates  the
          intermediate  output;  see  groff_out(5).   Then  groff  calls a
          postprocessor to convert  troff's  intermediate  output  to  its
          final format.  Real devices in groff are

                 dvi    TeX DVI format (postprocessor is grodvi).

                 html
                 xhtml  HTML  and  XHTML  output (preprocessors are soelim
                        and pre-grohtml, postprocessor is post-grohtml).

                 lbp    Canon CAPSL printers (LBP-4 and LBP-8 series laser
                        printers; postprocessor is grolbp).

                 lj4    HP LaserJet4 compatible (or other PCL5 compatible)
                        printers (postprocessor is grolj4).

                 ps     PostScript output (postprocessor is grops).

                 pdf    Portable    Document    Format    (PDF)     output
                        (postprocessor is gropdf).

          For  the  following  TTY output devices (postprocessor is always
          grotty), -T selects the output encoding:

                 ascii  7bit ASCII.

                 cp1047 Latin-1 character set for EBCDIC hosts.

                 latin1 ISO 8859-1.

                 utf8   Unicode character set  in  UTF-8  encoding.   This
                        mode has the most useful fonts for TTY mode, so it
                        is the best mode for TTY output.

          The following arguments select gxditview as the  'postprocessor'
          (it is rather a viewing program):

                 X75    75dpi resolution, 10pt document base font.

                 X75-12 75dpi resolution, 12pt document base font.

                 X100   100dpi resolution, 10pt document base font.

                 X100-12
                        100dpi resolution, 12pt document base font.

          The default device is ps.

   -U     Unsafe  mode.  Reverts to the (old) unsafe behaviour; see option
          -S.

   -v
   --version
          Output version information of groff and of all programs that are
          run  by  it;  that  is,  the given command line is parsed in the
          usual way, passing -v to all subprograms.

   -V     Output the pipeline that would be run by  groff  (as  a  wrapper
          program)  on  the  standard  output,  but do not execute it.  If
          given more than once, the  commands  are  both  printed  on  the
          standard error and run.

   -X     Use  gxditview  instead  of  using  the  usual  postprocessor to
          (pre)view a document.  The printing spooler behavior as outlined
          with  options  -l  and  -L  is  carried  over to gxditview(1) by
          determining  an  argument  for  the  -printCommand   option   of
          gxditview(1).   This  sets  the  default  Print  action  and the
          corresponding menu entry to that value.  -X only  produces  good
          results  with -Tps, -TX75, -TX75-12, -TX100, and -TX100-12.  The
          default resolution for previewing -Tps output is 75dpi; this can
          be  changed  by passing the -resolution option to gxditview, for
          example

                 groff -X -P-resolution -P100 -man foo.1

   -z     Suppress output generated by troff.   Only  error  messages  are
          printed.

   -Z     Do  not  automatically  postprocess groff intermediate output in
          the usual manner.  This will cause the troff output to appear on
          standard  output,  replacing the usual postprocessor output; see
          groff_out(5).

   Transparent Options
   The following options are transparently handed over  to  the  formatter
   program  troff that is called by groff subsequently.  These options are
   described in more detail in troff(1).

   -a     ASCII approximation of output.

   -b     Backtrace on error or warning.

   -c     Disable color output.  Please consult the grotty(1) man page for
          more details.

   -C     Enable compatibility mode.

   -d cs
   -d name=s
          Define string.

   -E     Disable troff error messages.

   -f fam Set default font family.

   -F dir Set path for font DESC files.

   -i     Process standard input after the specified input files.

   -m name
          Include   macro   file   name.tmac   (or  tmac.name);  see  also
          groff_tmac(5).

   -M dir Path for macro files.

   -n num Number the first page num.

   -o list
          Output only pages in list.

   -r cn
   -r name=n
          Set number register.

   -w name
          Enable warning name.  See troff(1) for names.

   -W name
          disable warning name.  See troff(1) for names.

USING GROFF

   The groff system implements the infrastructure of classical  roff;  see
   roff(7) for a survey on how a roff system works in general.  Due to the
   front-end programs available within the groff system,  using  groff  is
   much easier than classical roff.  This section gives an overview of the
   parts that constitute the groff system.  It  complements  roff(7)  with
   groff-specific  features.   This  section can be regarded as a guide to
   the documentation around the groff system.

   Paper Size
   The virtual paper size used by troff to format the input is  controlled
   globally  with  the  requests .po, .pl, and .ll.  See groff_tmac(5) for
   the 'papersize' macro package which provides a convenient interface.

   The physical paper size, giving the  actual  dimensions  of  the  paper
   sheets,  is  controlled  by  output devices like grops with the command
   line options -p and -l.  See groff_font(5) and the  man  pages  of  the
   output devices for more details.  groff uses the command line option -P
   to pass options to output devices; for example, the  following  selects
   A4 paper in landscape orientation for the PS device:

          groff -Tps -P-pa4 -P-l ...

   Front-ends
   The  groff program is a wrapper around the troff(1) program.  It allows
   to specify the preprocessors by command line options and  automatically
   runs  the  postprocessor  that  is appropriate for the selected device.
   Doing so, the sometimes tedious piping mechanism of  classical  roff(7)
   can be avoided.

   The  grog(1) program can be used for guessing the correct groff command
   line to format a file.

   The groffer(1) program is an allround-viewer for groff  files  and  man
   pages.

   Preprocessors
   The   groff   preprocessors  are  reimplementations  of  the  classical
   preprocessors with moderate  extensions.   The  standard  preprocessors
   distributed with the groff package are

   eqn(1) for mathematical formulae,

   grn(1) for including gremlin(1) pictures,

   pic(1) for drawing diagrams,

   chem(1)
          for chemical structure diagrams,

   refer(1)
          for bibliographic references,

   soelim(1)
          for including macro files from standard locations,

   and

   tbl(1) for tables.

   A new preprocessor not available in classical troff is preconv(1) which
   converts various input encodings to something groff can understand.  It
   is always run first before any other preprocessor.

   Besides   these,   there  are  some  internal  preprocessors  that  are
   automatically run with some devices.  These aren't visible to the user.

   Macro Packages
   Macro packages  can  be  included  by  option  -m.   The  groff  system
   implements and extends all classical macro packages in a compatible way
   and adds some packages of  its  own.   Actually,  the  following  macro
   packages come with groff:

   man    The  traditional  man  page format; see groff_man(7).  It can be
          specified on the command line as -man or -m man.

   mandoc The general package for man pages; it  automatically  recognizes
          whether  the  documents  uses  the  man  or  the mdoc format and
          branches  to  the  corresponding  macro  package.   It  can   be
          specified on the command line as -mandoc or -m mandoc.

   mdoc   The  BSD-style  man  page  format; see groff_mdoc(7).  It can be
          specified on the command line as -mdoc or -m mdoc.

   me     The classical me document format; see groff_me(7).   It  can  be
          specified on the command line as -me or -m me.

   mm     The  classical  mm  document format; see groff_mm(7).  It can be
          specified on the command line as -mm or -m mm.

   ms     The classical ms document format; see groff_ms(7).   It  can  be
          specified on the command line as -ms or -m ms.

   www    HTML-like macros for inclusion in arbitrary groff documents; see
          groff_www(7).

   Details on the naming of macro files and their placement can  be  found
   in  groff_tmac(5);  this  man  page  also  documents  some other, minor
   auxiliary macro packages not mentioned here.

   Programming Language
   General concepts common to all roff programming languages are described
   in roff(7).

   The  groff extensions to the classical troff language are documented in
   groff_diff(7).

   The groff language as a whole is described in  the  (still  incomplete)
   groff  info  file;  a  short  (but  complete) reference can be found in
   groff(7).

   Formatters
   The central roff formatter within the groff  system  is  troff(1).   It
   provides the features of both the classical troff and nroff, as well as
   the groff extensions.  The command line option -C switches  troff  into
   compatibility  mode  which  tries  to emulate classical roff as much as
   possible.

   There is  a  shell  script  nroff(1)  that  emulates  the  behavior  of
   classical  nroff.   It  tries to automatically select the proper output
   encoding, according to the current locale.

   The formatter program generates intermediate output; see groff_out(7).

   Devices
   In roff, the output targets are called devices.   A  device  can  be  a
   piece  of  hardware,  e.g.,  a  printer,  or a software file format.  A
   device is specified by  the  option  -T.   The  groff  devices  are  as
   follows.

   ascii  Text output using the ascii(7) character set.

   cp1047 Text  output using the EBCDIC code page IBM cp1047 (e.g., OS/390
          Unix).

   dvi    TeX DVI format.

   html   HTML output.

   latin1 Text output using the ISO Latin-1 (ISO  8859-1)  character  set;
          see iso_8859_1(7).

   lbp    Output  for  Canon  CAPSL printers (LBP-4 and LBP-8 series laser
          printers).

   lj4    HP LaserJet4-compatible (or other PCL5-compatible) printers.

   ps     PostScript output; suitable for  printers  and  previewers  like
          gv(1).

   pdf    PDF files; suitable for viewing with tools such as evince(1) and
          okular(1).

   utf8   Text output using the Unicode (ISO  10646)  character  set  with
          UTF-8 encoding; see unicode(7).

   xhtml  XHTML output.

   X75    75dpi  X  Window  System  output  suitable  for  the  previewers
          xditview(1x) and gxditview(1).  A variant for  a  12pt  document
          base font is X75-12.

   X100   100dpi  X  Window  System  output  suitable  for  the previewers
          xditview(1x) and gxditview(1).  A variant for  a  12pt  document
          base font is X100-12.

   The  postprocessor  to be used for a device is specified by the postpro
   command in the device description file; see groff_font(5).  This can be
   overridden with the -X option.

   The default device is ps.

   Postprocessors
   groff provides 3 hardware postprocessors:

   grolbp(1)
          for some Canon printers,

   grolj4(1)
          for printers compatible to the HP LaserJet 4 and PCL5,

   grotty(1)
          for  text output using various encodings, e.g., on text-oriented
          terminals or line-printers.

   Today, most printing or drawing hardware is handled  by  the  operating
   system, by device drivers, or by software interfaces, usually accepting
   PostScript.  Consequently, there isn't an urgent need for more hardware
   device postprocessors.

   The  groff  software  devices  for  conversion into other document file
   formats are

   grodvi(1)
          for the DVI format,

   grohtml(1)
          for HTML and XHTML formats,

   grops(1)
          for PostScript.

   gropdf(1)
          for PDF.

   Combined with the many existing free conversion tools  this  should  be
   sufficient to convert a troff document into virtually any existing data
   format.

   Utilities
   The following utility programs around groff are available.

   addftinfo(1)
          Add information to troff font description  files  for  use  with
          groff.

   afmtodit(1)
          Create font description files for PostScript device.

   eqn2graph(1)
          Convert an eqn image into a cropped image.

   gdiffmk(1)
          Mark differences between groff, nroff, or troff files.

   grap2graph(1)
          Convert a grap diagram into a cropped bitmap image.

   groffer(1)
          General viewer program for groff files and man pages.

   gxditview(1)
          The groff X viewer, the GNU version of xditview.

   hpftodit(1)
          Create font description files for lj4 device.

   indxbib(1)
          Make inverted index for bibliographic databases.

   lkbib(1)
          Search bibliographic databases.

   lookbib(1)
          Interactively search bibliographic databases.

   pdfroff(1)
          Create PDF documents using groff.

   pfbtops(1)
          Translate a PostScript font in .pfb format to ASCII.

   pic2graph(1)
          Convert a pic diagram into a cropped image.

   tfmtodit(1)
          Create font description files for TeX DVI device.

   xditview(1x)
          roff viewer distributed with X window.

   xtotroff(1)
          Convert X font metrics into GNU troff font metrics.

ENVIRONMENT

   Normally,  the path separator in the following environment variables is
   the colon; this may  vary  depending  on  the  operating  system.   For
   example, DOS and Windows use a semicolon instead.

   GROFF_BIN_PATH
          This  search  path, followed by $PATH, is used for commands that
          are executed by groff.  If it is  not  set  then  the  directory
          where the groff binaries were installed is prepended to PATH.

   GROFF_COMMAND_PREFIX
          When  there  is  a need to run different roff implementations at
          the same time groff provides the facility to prepend a prefix to
          most  of  its  programs that could provoke name clashings at run
          time (default is to have none).  Historically, this  prefix  was
          the  character  g,  but it can be anything.  For example, gtroff
          stood for groff's troff, gtbl for the groff version of tbl.   By
          setting  GROFF_COMMAND_PREFIX to different values, the different
          roff installations can be addressed.  More exactly, if it is set
          to  prefix  xxx then groff as a wrapper program internally calls
          xxxtroff  instead  of  troff.   This   also   applies   to   the
          preprocessors  eqn,  grn,  pic,  refer,  tbl, soelim, and to the
          utilities indxbib and lookbib.  This feature does not  apply  to
          any  programs  different from the ones above (most notably groff
          itself) since they are unique to the groff package.

   GROFF_ENCODING
          The value of this environment value is  passed  to  the  preconv
          preprocessor  to  select  the  encoding of input files.  Setting
          this option implies groff's command line  option  -k  (this  is,
          groff  actually  always calls preconv).  If set without a value,
          groff calls preconv without arguments.  An explicit  -K  command
          line   option   overrides  the  value  of  GROFF_ENCODING.   See
          preconv(1) for details.

   GROFF_FONT_PATH
          A list of  directories  in  which  to  search  for  the  devname
          directory  in  addition  to  the default ones.  See troff(1) and
          groff_font(5) for more details.

   GROFF_TMAC_PATH
          A list of directories in which to  search  for  macro  files  in
          addition   to   the   default  directories.   See  troff(1)  and
          groff_tmac(5) for more details.

   GROFF_TMPDIR
          The directory in which temporary files are created.  If this  is
          not  set  but the environment variable TMPDIR instead, temporary
          files are created in  the  directory  $TMPDIR.   On  MS-DOS  and
          Windows 32 platforms, the environment variables TMP and TEMP (in
          that order) are searched also, after  GROFF_TMPDIR  and  TMPDIR.
          Otherwise,  temporary  files are created in /tmp.  The refer(1),
          groffer(1), grohtml(1),  and  grops(1)  commands  use  temporary
          files.

   GROFF_TYPESETTER
          Preset  the default device.  If this is not set the ps device is
          used as default.  This device name is overwritten by the  option
          -T.

EXAMPLES

   The  following  example illustrates the power of the groff program as a
   wrapper around troff.

   To process a roff file using the preprocessors tbl and pic and  the  me
   macro set, classical troff had to be called by

          pic foo.me | tbl | troff -me -Tlatin1 | grotty

   Using groff, this pipe can be shortened to the equivalent command

          groff -p -t -me -T latin1 foo.me

   An  even  easier  way  to  call  this  is  to  use grog(1) to guess the
   preprocessor and macro options and execute the  generated  command  (by
   using backquotes to specify shell command substitution)

          `grog -Tlatin1 foo.me`

   The simplest way is to view the contents in an automated way by calling

          groffer foo.me

BUGS

   On  EBCDIC  hosts  (e.g., OS/390 Unix), output devices ascii and latin1
   aren't available.  Similarly, output for EBCDIC code page cp1047 is not
   available on ASCII based operating systems.

   Report  bugs  to the groff mailing list bug-groff@gnu.org.  Include a
   complete, self-contained example that allows the bug to be  reproduced,
   and say which version of groff you are using.

POSITIONS FROM INSTALLATION

   There  are  some  directories  in  which groff installs all of its data
   files.  Due to different installation  habits  on  different  operating
   systems,  their  locations are not absolutely fixed, but their function
   is clearly defined and coincides on all systems.

   Collection of Installation Directories
   This section describes the position of all files of the  groff  package
   after the installation --- got from Makefile.comm at the top of the groff
   source package.

   /usr/dict/papers/Ind
          index directory and index name

   /usr/lib/font
          legacy font directory

   /usr/bin
          directory for binary programs

   /usr/lib/groff/site-tmac
          system tmac directory

   /usr/share/doc/groff-base
          documentation directory

   /usr/share/doc/groff-base/examples
          directory for examples

   /usr/share/doc/groff-base/html
          documentation directory for html files

   /usr/share/doc/groff-base/pdf
          documentation directory for pdf files

   /usr/share/groff/1.22.3
          data subdirectory

   /usr/share/groff/1.22.3/eign
          file for common words

   /usr/share/groff/1.22.3/font
          directory for fonts

   /usr/share/groff/1.22.3/oldfont
          directory for old fonts

   /usr/share/groff/1.22.3/tmac
          tmac directory

   /usr/share/groff/1.22.3/tmac/mm
          mm tmac directory

   /usr/share/groff/site-font
          local font directory

   /usr/share/groff/site-tmac
          local tmac directory

   groff Macro Directory
   This contains all information related to  macro  packages.   Note  that
   more  than a single directory is searched for those files as documented
   in groff_tmac(5).  For the groff  installation  corresponding  to  this
   document, it is located at /usr/share/groff/1.22.3/tmac.  The following
   files contained in the groff macro directory have a special meaning:

   troffrc
          Initialization file for troff.  This  is  interpreted  by  troff
          before reading the macro sets and any input.

   troffrc-end
          Final startup file for troff.  It is parsed after all macro sets
          have been read.

   name.tmac
   tmac.name
          Macro file for macro package name.

   groff Font Directory
   This contains all information related to  output  devices.   Note  that
   more than a single directory is searched for those files; see troff(1).
   For the groff  installation  corresponding  to  this  document,  it  is
   located at /usr/share/groff/1.22.3/font.  The following files contained
   in the groff font directory have a special meaning:

   devname/DESC
          Device description file for device name, see groff_font(5).

   devname/F
          Font file for font F of device name.

AVAILABILITY

   Information on how to get groff and related information is available at
   the groff GNU website http://www.gnu.org/software/groff.

   Three groff mailing lists are available:

          for reporting bugs bug-groff@gnu.org.

          for general discussion of groff, groff@gnu.org.

          the  groff commit list groff-commit@ffii.org, a read-only list
          showing logs of commitments to the groff repository.

   Details on repository access and much more can be  found  in  the  file
   README at the top directory of the groff source package.

   There is a free implementation of the grap preprocessor, written by Ted
   Faber faber@lunabase.org.  The actual version can  be  found  at  the
   grap   website   http://www.lunabase.org/~faber/Vault/software/grap/.
   This is the only grap version supported by groff.

SEE ALSO

   The groff info file contains all information on the groff system within
   a single document, providing many examples and background information.
   See info(1) on how to read it.

   Due to its complex structure, the groff system has many man pages.
   They can be read with man(1) or groffer(1).

   But there are special sections of man-pages.  groff has man-pages in
   sections 1, 5,and 7.  When there are several man-pages with the same
   name in the same man section, the one with the lowest section is should
   as first.  The other man-pages can be shown anyway by adding the
   section number as argument before the man-page name.  Reading the man-
   page about the groff language is done by one of
          man 7 groff
          groffer 7 groff

   Introduction, history and further readings:
          roff(7).

   Viewer for groff files:
          groffer(1), gxditview(1), xditview(1x).

   Wrapper programs for formatters:
          groff(1), grog(1).

   Roff preprocessors:
          eqn(1), grn(1), pic(1), chem(1), preconv(1), refer(1),
          soelim(1), tbl(1), grap(1).

   Roff language with the groff extensions:
          groff(7), groff_char(7), groff_diff(7), groff_font(5).

   Roff formatter programs:
          nroff(1), troff(1), ditroff(7).

   The intermediate output language:
          groff_out(7).

   Postprocessors for the output devices:
          grodvi(1), grohtml(1), grolbp(1), grolj4(1), lj4_font(5),
          grops(1), gropdf(1), grotty(1).

   Groff macro packages and macro-specific utilities:
          groff_tmac(5), groff_man(7), groff_mdoc(7), groff_me(7),
          groff_mm(7), groff_mmse(7) (only in Swedish locales),
          groff_mom(7), groff_ms(7), groff_www(7), groff_trace(7),
          mmroff(7).

   The following utilities are available:
          addftinfo(1), afmtodit(1), eqn2graph(1), gdiffmk(1),
          grap2graph(1), groffer(1), gxditview(1), hpftodit(1),
          indxbib(1), lkbib(1), lookbib(1), pdfroff(1), pfbtops(1),
          pic2graph(1), tfmtodit(1), xtotroff(1).

COPYING (LICENSE)

   Copyright  1989-2014 Free Software Foundation, Inc.

   Rewritten in 2002 by Bernd Warken <groff-bernd.warken-72@web.de>

   This document is part of groff, a free GNU software project.

   Permission is granted to copy, distribute and/or modify this document
   under the terms of the GNU Free Documentation License, Version 1.3 or
   any later version published by the Free Software Foundation; with the
   Invariant Sections being the macro definition or .co and .au, with no
   Front-Cover Texts, and with no Back-Cover Texts.

   A copy of the Free Documentation License is included as a file called
   FDL in the main directory of the groff source package.

   It is also available in the internet at the GNU copyleft site http://
   www.gnu.org/copyleft/fdl.html.

AUTHORS

   This document is based on the original groff man page written by James
   Clark jjc@jclark.com.  It was rewritten, enhanced, and put under the
   FDL license by Bernd Warken <groff-bernd.warken-72@web.de>.  It is
   maintained by Werner Lemberg wl@gnu.org.





Opportunity


Personal Opportunity - Free software gives you access to billions of dollars of software at no cost. Use this software for your business, personal use or to develop a profitable skill. Access to source code provides access to a level of capabilities/information that companies protect though copyrights. Open source is a core component of the Internet and it is available to you. Leverage the billions of dollars in resources and capabilities to build a career, establish a business or change the world. The potential is endless for those who understand the opportunity.

Business Opportunity - Goldman Sachs, IBM and countless large corporations are leveraging open source to reduce costs, develop products and increase their bottom lines. Learn what these companies know about open source and how open source can give you the advantage.





Free Software


Free Software provides computer programs and capabilities at no cost but more importantly, it provides the freedom to run, edit, contribute to, and share the software. The importance of free software is a matter of access, not price. Software at no cost is a benefit but ownership rights to the software and source code is far more significant.


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Free Books


The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.


Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.





Education


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Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.