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  Frequently Asked Questions About Fonts
  ----------------------------------------------------------------------
  Compiled by Norman Walsh
  Copyright (C) 1992, 93 by Norman Walsh .
  
Subject: Table of Contents

  1. General Information
    1.1. Font Houses
    1.2. What's the difference between all these font formats?
    1.3. What about "Multiple Master" fonts?
    1.4. Is there a methodology to describe and classify typefaces?
    1.5. What is the "f" shaped "s" called?
    1.6. What about "Colonial" Typefaces?
    1.7. Where can I get ... fonts.
    1.8. Where can I get fonts for non-Roman alphabets?
    1.10. How can I convert my ... font to ... format?

Subject: 1. General Information
  
  Many FAQs, including this one, are available by anonymous ftp from
  rtfm.mit.edu in the directory pub/usenet/news.answers.  Each posted
  section of the FAQ is archived under the name that appears in the
  "Archive-name" header at the top of the article.
  
  This FAQ is a work in progress.  If you have any suggestions, I would be
  delighted to hear them.
  
  This FAQ is maintained in TeXinfo format.  A Perl script constructs the
  postable FAQ from the TeXinfo sources.  TeX DVI, PostScript, and Info
  versions of this FAQ are available from ftp.shsu.edu in
  /tex-archive/help/comp-fonts-FAQ.  A "Gopher" server is also maintained
  at shsu.edu which can provide interactive access to the FAQ.  Finally,
  an online, hypertext version of the FAQ is maintained (experimentally)
  on jasper.ora.com where an HTTP server runs.  For example, point
  XMosaic (or a similar WWW browser) to http://jasper.ora.com/.
  
  The posted version of the FAQ is organized in a quasi-digest format so
  that it is easy to find the questions you are interested in.  All
  questions that appear in the table of contents can be found by searching
  for the word "Subject:" followed by the question number.
  
  The "TeXinfo" distribution from the Free Software Foundation contains a
  program called "Info" that can be used to read the Info version of the
  FAQ in a hypertext manner.  The "TeXinfo" distribution can be obtained
  from prep.ai.mit.edu in the /pub/gnu directory.  At the time of this
  writing, texinfo-2.16.tar.gz is the most recent version.  Info files
  can also be read in hypertext form by GNU Emacs.
  
  Future versions of the FAQ will make more use of the hypertext
  capabilities provided by the Info format.  At present, the FAQ is
  organized as a simple tree.  A plain ASCII, postable version of the FAQ
  will always be maintained.
  
  All trademarks used in this document are the trademarks of their
  respective owners.
  
  Standard disclaimers apply.
  
Subject: 1.1. Font Houses
  
  This section will be expanded on in the future.  It contains notes about
  various commercial font houses.
  
  Compugraphic
  ============
  
  See "Miles, Agfa Division"
  
  Miles, Agfa Division
  ====================
  
  Compugraphic which was for a while the Compugraphic division of Agfa,
  is now calling itself "Miles, Agfa Division" (yes, the Miles drug
  company), since CG's off-shore parent Agfa has been absorbed by Miles.
  So typographically speaking, Compugraphic, CG, Agfa, A-G ag, and Miles
  all refer to the same company and font library. Their proprietary fonts
  are still CG Xyz, but the name is Miles Agfa.
  
Subject: 1.2. What's the difference between all these font formats?
  
  This question is not trivial to answer.  It's analogous to asking what
  the difference is between various graphics image file formats.  The
  short, somewhat pragmatic answer, is simply that they are different
  ways of representing the same "information" and some of them will work
  with your software/printer and others won't.
  
  At one level, there are two major sorts of fonts: bitmapped and outline
  (scalable).  Bitmapped fonts are falling out of fashion as various
  outline technologies grow in popularity and support.
  
  Bitmapped fonts represent each character as a rectangular grid of
  pixels.  The bitmap for each character indicates precisely what pixels
  should be on and off.  Printing a bitmapped character is simply a
  matter of blasting the right bits out to the printer.  There are a
  number of disadvantages to this approach.  The bitmap represents a
  particular instance of the character at a particular size and
  resolution.  It is very difficult to change the size, shape, or
  resolution of a bitmapped character without significant loss of quality
  in the image.  On the other hand, it's easy to do things like shading
  and filling with bitmapped characters.
  
  Outline fonts represent each character mathematically as a series of
  lines, curves, and 'hints'.  When a character from an outline font is
  to be printed, it must be 'rasterized' into a bitmap "on the fly".
  PostScript printers, for example, do this in the print engine.  If the
  "engine" in the output device cannot do the rasterizing, some front end
  has to do it first.  Many of the disadvantages that are inherent in the
  bitmapped format are not present in outline fonts at all.  Because an
  outline font is represented mathematically, it can be drawn at any
  reasonable size.  At small sizes, the font renderer is guided by the
  'hints' in the font; at very small sizes, particularly on
  low-resolution output devices such as screens, automatically scaled
  fonts become unreadable, and hand-tuned bitmaps are a better choice (if
  they are available).  Additionally, because it is rasterized "on
  demand," the font can be adjusted for different resolutions and 'aspect
  ratios'.
  
  Werenfried Spit adds the following remark:
  
  Well designed fonts are not scalable. I.e. a well designed 5pt font is
  not simply its 10pt counterpart 50% scaled down. (One can verify this
  by blowing up some small print in a copier and compare it with large
  print; or see the example for computer modern in D.E. Knuth's TeXbook.)
  Although this fact has no direct implications for any of the two
  methods of font representation it has an indirect one: users and word
  processor designers tend to blow up their 10pt fonts to 20pt or scale
  them down to 5pt given this possibility.  Subtle details, but well...
  
  LaserJet .SFP and .SFL files, TeX PK, PXL, and GF files, Macintosh
  Screen Fonts, and GEM .GFX files are all examples of bitmapped font
  formats.
  
  PostScript Type 1, Type 3, and Type 5 fonts, Nimbus Q fonts, TrueType
  fonts, Sun F3, MetaFont .mf files, and LaserJet .SFS files are all
  examples of outline font formats.
  
  Neither of these lists is even close to being exhaustive.
  
  To complicate the issue further, identical formats on different
  platforms are not necessarily the same.  For example Type 1 fonts on
  the Macintosh are not directly usable under MS-DOS or Unix, and
  vice-versa.
  
  It has been pointed out that the following description shows signs of
  its age (for example, the eexec encryption has been thoroughly hacked).
  I don't dispute the observation and I encourage anyone with the
  knowledge and time to submit a more up to date description.
  
  It has further been suggested that this commentary is biased toward
  Kingsley/ATF.  The omission of details about Bitstream (and possibly
  Bauer) may be considered serious since their software lies inside many
  3rd-party PostScript interpreters.
  
  The moderators of this FAQ would gladly accept other descriptions/
  explanations/viewpoints on the issues discussed in this (and every
  other) section.
  
  [Ed Note: Liam R. E. Quin supplied many changes to the following
  section in an attempt to bring it up to date.  Hopefully it is a better
  reflection of the state of the world today (12/07/92) than it was in
  earlier FAQs]