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+% this is from the Companion, p108, but simply doesn't work!
+% In the tabular, LaTeX complains that \temp is undefined.
+\newcommand{\PreserveBackslash}[1]{\let\temp=\\#1\let\\=\temp}
+\let\PBS=\PreserveBackslash
+% This ought to be a package, but I don't think it's been unpgraded yet.
+\title{HTML \& \TeX: Making them sweat}
+\author[Peter Flynn]{Peter Flynn\\University College, Cork}
+\begin{Article}
+\begin{abstract}
+
+\noindent HTML is often criticised for its presentation-oriented conception.
+But it does contain sufficient structural information for many
+everyday purposes and this has led to its development into a more
+stable form. Future platforms for the World Wide Web may support other
+applications of SGML, and the present climate of popularity of the Web
+is a suitable opportunity for consolidation of the more stable
+features. \TeX\ is pre-eminently stable and provides an ideal
+companion for the process of translating HTML into print.
+
+\end{abstract}
+
+\section{Markup}
+
+HTML, a HyperText Markup Language\cite{html-spec}, is the language used
+to structure text files for use in the World Wide Web, an Internet-based
+hypertext and multimedia distributed information system. HTML is an
+application of SGML, the Standard Generalized Markup Language, ISO
+8879\cite{iso-sgml}. Contrary to popular belief, neither SGML nor HTML
+is new: SGML gained International Standard status in 1986 and HTML has
+been in use since 1989.
+\begin{figure*}
+\begin{verbatim}
+#! /bin/sh
+
+echo Content-type: text/html
+echo
+
+cat <<EOH
+<html><head><title>Date and time</title></head><body><p>It is now
+EOH
+date
+cat <<EOT
+</p></body></html>
+EOT
+\end{verbatim}
+\caption{Example of a Unix shell script to return the date and time as
+a HTML file}
+\label{script}
+\end{figure*}
+
+SGML is a specification for writing descriptions of text structure. In
+itself SGML does not \emph{do} anything, any more than, say, Kernighan
+and Ritchie's specification of the C~language\cite{krc} \emph{does}
+anything: users and implementors have to do something \emph{with}
+it. It has been slow to achieve popularity, partly because writing
+effective Document Type Descriptions (DTDs) is a non-trivial task, and
+partly because software to make full use of its facilities has
+traditionally been expensive. It was therefore seen as a `big business
+only' solution to text-handling problems until the popularisation of
+HTML owing to increased use of the World Wide Web. Since 1992 the
+software position has also improved considerably~--- an extensive list of
+tools is maintained by Steve Pfeffer at UIO\cite{sgml-tools}.
+
+\section{The World Wide Web}
+
+WWW (W3 or just `the Web') is a client-server application on the
+Internet. Users' clients (`browsers') request files from servers run
+by information providers and display them, using the HTML markup
+embedded in the text to render the formatting. Some of the markup can
+provide filenames for the retrieval of graphics as illustrations, or
+act as anchor-points for links to other documents, which can be
+further text, or graphics, sound or motion video. This latter
+capability gives the Web a hypertext and multimedia dimension, and
+allows crosslinking of files almost anywhere on the Internet.
+
+Because the HTML files are plain text with embedded plain text markup,
+in traditional SGML manner, they are immediately portable between
+arbitrary makes and models of computer or operating system, making the
+Web one of the first genuinely portable, multiplatform applications of
+its kind.
+
+\subsection{HTML Markup}
+
+An example of simple markup and an appropriate rendering is
+illustrated in Figure~\ref{html-example}. The conventions of SGML's
+Reference Concrete Syntax\cite{iso-sgml} are used, so markup `tags'
+are enclosed in angle brackets (less-than and greater-than signs), in
+pairs surrounding the text to which they refer, with the end-tag being
+preceded by a slash or solidus immediately after its opening angle
+bracket.
+
+\begin{figure*}
+\begin{verbatim}
+<html>
+ <head>
+ <title>Fleet Street Eats</title>
+ </head>
+ <body>
+ <h1>Where to eat in Fleet Street</h1>
+ <p>There are many restaurants in the City, from
+ fast-food joints to <i>haute cuisine</i>.</p>
+ ...
+\end{verbatim}
+\vspace{1ex}
+\hrule
+\vspace{1em}
+\begin{flushright}
+\begin{small}
+{\bf Document title:} {\tt Fleet Street Eats}
+\end{small}
+\end{flushright}
+\section*{Where to eat in Fleet Street}
+There are many restaurants in the City, from
+fast-food joints to {\it haute cuisine\/}.\newline\dots
+\caption{Example of HTML markup and possible rendering}
+\label{html-example}
+\end{figure*}
+
+The rendering is left almost entirely to the user's client program, as
+there are almost no facilities within HTML for the expression of
+appearance apart from a minimal indication of font change (italics,
+boldface and typewriter-type). Indeed, most recent browsers allow the
+{\em user} arbitrary control over which fonts, sizes and colours
+should be used to instantiate the tagged elements of text.
+
+\subsection{Implementation}
+
+HTML was devised for the Web by non-SGML-experts who saw it as an
+ideal mechanism for implementing plain-text portability while
+preserving sufficient structural information for online rendering: one
+of the classical reasons for adopting SGML. It is now becoming
+standardised by an IETF working group who have produced a draft
+specification in the form of a formal DTD\cite{html-spec}. Because of
+the need to allow this specification to model existing `legacy'
+documents (most of which would be regarded as fragments rather than
+document instances), as well as provide for more robust usage, the
+current DTD has two modes: a non-rigorous `deprecated' mode for
+describing the legacy and a `recommended' mode for creating and
+maintaining files in conventional form.
+
+HTML is sufficient for minimal documents, providing the structural and
+visual features shown in Figure~\ref{html-tags}. A future version
+(3.0) is being developed by the IETF Working Group, which will allow
+the description of mathematics, tables and some additional visual- and
+content-oriented features.
+
+\begin{figure*}
+\begin{tabular}{>{\tt}l>{\PBS\raggedright\hspace{0pt}\baselineskip=10pt}p{1in}|>{\tt}l>{\PBS\raggedright\hspace{0pt}\baselineskip=10pt}p{1in}|>{\tt}l>{\PBS\raggedright\hspace{0pt}\baselineskip=10pt}p{1in}}
+\multicolumn{2}{c|}{{\bf Structural}}&\multicolumn{2}{c|}{{\bf Descriptive}}&\multicolumn{2}{c}{{\bf Visual}} \\ [3pt]
+html &document type&
+ a &hypertext link anchor-point&
+ b &bold type \\
+\quad head &document header&
+ cite &citations&
+ br &forced line-break \\
+\quad title &document title&
+ code &computer code&
+ hr &horizontal rule \\
+\quad base &root address for incomplete hypertext references&
+ em &emphasis&
+ i &italics \\
+\quad meta &specification of mapped headers&
+ kbd &keyboard input&
+ tt &typewriter type \\
+\quad link &relationship of document to outside world&
+ samp &sample of input&
+ img &illustrations \\
+\quad isindex &specifies a processable document which can take an argument&
+ strong &strong emphasis&
+ &\\
+ &&
+ var &program variable&
+ &\\
+body &contains all the text&
+ &&
+ &\\
+\quad h1\dots h6&six levels of section heading&
+ &&
+ &\\
+\quad p &paragraph&
+ &&
+ &\\
+\quad pre &preformatted text&
+ &&
+ &\\
+\quad blockquote&block quotations&
+ {\bf Form-fill}&&
+ {\bf Obsolete:}&\\
+\quad address &addresses&
+ form &contains a form&
+ listing &use {\tt pre} \\
+\quad ol &ordered lists&
+ textarea &free-text entry &
+ xmp &use {\tt pre} \\
+\quad ul &unordered lists&
+ input &input field (text, checkbox, radio button, {\it etc}&
+ plaintext &use {\tt pre} \\
+\quad menu &menu lists&
+ select &drop-down menu&
+ nextid &editing control \\
+\quad dir &directory lists&
+ \quad option &menu item&
+ dfn &definition of term\\
+\qquad li &list item&
+ &&
+ &\\
+\quad dl &definition lists&
+ &&
+ &\\
+\qquad dt &definition list term&
+ &&
+ &\\
+\qquad dd &definition list description&
+ &&
+ &\\
+\end{tabular}
+\caption{Markup available in HTML 2.0 (indentation implies the item
+must occur within the domain of its [non-indented] parent)}
+\label{html-tags}
+\end{figure*}
+
+Despite the coming improvements, HTML is likely to be joined in the
+Web by other DTDs in future. One well-known SGML software house
+already has a prototype browser which can handle instances of
+arbitrary DTDs, given sufficient formatting information. This would
+make it possible to use the Web for transmission and display of
+documents using other SGML applications such as CALS (US Military),
+DocBook (O'Reilly/Davenport), the TEI (Text Encoding Initiative) and
+corporation-specific DTDs (such as those of Elsevier).\label{otherdtds}
+
+The next version of the DTD, HTML3, contains specifications for
+mathematics, tables and some additional elements for
+content-descriptive material, as well as a few extra visual keys such
+as an {\tt ALIGN} attribute for positional specification. Most of this
+work is being implemented on a test basis in the Arena browser (Unix/X
+only at the moment) at CERN.
+
+Although Web browsers can reference files by any of several methods
+(HTTP, the Web's `native' protocol; FTP; Telnet; Gopher; WAIS; and
+others) by using the URL (Universal Resource Locator: a form of file
+address on the Internet), the most powerful tool lies at the server
+end: the ability of servers to execute scripts, provided their output
+is HTML. A trivial example is shown in Figure~\ref{script}, which
+returns the date and time.
+
+Such a script can contain arbitrary processing, including the
+invocation of command-line programs and the passing of arguments. Data
+can be gathered from the user either with the \verb+<isindex>+ tag in
+the header, which causes a single-line data-entry field to appear, or
+with the more complex \verb+<form>+ element with scrollable text
+boxes, checkboxes, radio buttons and menus. In this manner, complete
+front-ends can be manufactured to drive data-retrieval engines of any
+kind, provided that they operate from the command line, and that the
+script returns their output in HTML\@. The user (and the browser) remain
+unaware that the result has been generated dynamically.
+
+\subsection{Presentation}
+
+HTML is criticised for being `presentation-oriented', but as can be
+seen from Figure~\ref{html-tags}, the overwhelming majority of the
+markup is structural or content-descriptive. However, this does not
+prevent the na\"\i ve or sophisticated author from using or abusing
+the markup in attempts to coerce browsers into displaying a specific
+visual instantiation, primarily because none of the browsers (with the
+partial exceptions of Arena and {\tt w3-mode} for GNU Emacs) performs
+any form of validation parsing, and will thus display any random
+assemblage of tags masquerading as HTML. This behaviour has misled
+even some eminent authorities to dismiss HTML as `not being SGML'.
+
+There is thus a conflict between the SGML purist on the one side, who
+decries any attempt at encoding visual appearance; and the uninformed
+author on the other, who has been unintentionally misled into thinking
+that HTML and the Web constitute some kind of glorified networked DTP
+system.
+
+The purists are few in number but eloquently vocal: however, in
+general, they acknowledge that visual keys can be included if they are
+carefully coded. A perceived requirement to allow an author to
+recommend the centering of an element is thus achieved in HTML3 by the
+\verb+align="center"+ attribute, rather than the unnecessary
+\verb+<center>+ element proposed by the authors of Netscape.
+
+The demands of the author are at their most marked in the approach of
+publishers and marketing users, who have been accustomed for the last
+550 years to exert absolute control over the final appearance of their
+text. But the Web is not paper, and the freedoms and constraints of
+the Press do not apply: it is as much a new medium as radio or
+television. For such an author to insist that she must be able to
+control the final display to the same extent as on paper is as
+pointless as insisting that a viewer with a black-and-white television
+must be able to see the colours in a commercial.
+
+The paradigm has been established that the browser controls the
+appearance, using the markup as guidelines. There is indeed no reason
+at all why attributes could not be added so that an author could write
+
+{\tt <h1 color=green font=LucidaBrightBoldItalic size=24 shading=50>}
+
+\noindent but the user of Lynx or WWW (two popular text-only browsers
+for terminal screens) would still only see the heading in fixed-width
+typewriter characters. The habit of insisting that everyone `must'
+see a particular typographic instantiation is an unfortunate result of
+a misinterpretation of the objective of the Web: to deliver
+information in a compact, portable and arbitrarily reprocessable form.
+
+But publishers accustomed to paper, insistent on `keeping control',
+have of course an entirely valid point, one with which the present
+author has great sympathy. Why should a carefully-prepared document be
+made a hames of by a typographically illiterate user who has set
+\verb+<h2>+ to display as 44pt Punk Bold in diagonal purple and green
+stripes?
+
+The solution probably lies in the implementation of style sheets,
+perhaps along the lines of those discussed by the authors of
+Arena\cite{arena-style}. They would in any case only be
+recommendations: not every user has a CD-ROM of Adobe or Monotype
+fonts. In any event, if 100\% control is essential, as in the display
+of typographic examples, all graphical browsers can be configured to
+spawn a window to display PostScript file, although the download time
+may be a strong disincentive.
+
+It is entirely possible that the control of content will
+ultimately prove a more attractive option than the control of
+appearance.
+
+\section{Publishing with HTML}
+
+Setting aside the unresolved questions of display, there are more
+pressing business problems about publishing on the Web.
+
+The authentication of users is being addressed at several levels, from
+simple, non-authoritative checks using {\tt identd} to the more complex
+username-and-password systems employed on some Web pages. From the
+user's end, the authentication of the data being accessed is equally
+important. The openness of the Internet in its raw form allows
+`spoofing' in both directions, so the emergence of protocols to
+provide checks is to be welcomed.
+
+The security of network-accessible texts from break-ins remains a
+concern to anyone providing high-value merchandise, and Web text is
+in this sense no different from any other computer data. Normal
+precautions must therefore be taken to prevent theft through
+other channels (such as remote lo\-gin), as distinct from theft
+perpetrated by falsification of Web access.
+
+There is a need for robust solutions to charging and billing for
+usage, and the secure transmission of financial data, including credit
+card numbers, digital signatures, and perhaps even EFT transactions.
+The Secure HTTP (SHTTP) mechanism being marketed by MCom and others is
+becoming popular as a way of achieving some of this, but the Internet
+must shed some of its image of lax controls and sloppy housekeeping if
+it is to achieve sufficient `respectability' to attract the business
+of those who are not networking specialists.
+
+The handling of copyright and the intellectual property of electronic
+texts remains, as ever, an unsolved problem. While copyright law can
+be used to provide a remedy for breach, the difficulty lies in
+preventing the breach occurring in the first place. The reason is that
+(as with other electronic mat\-er\-ial), copying and reproduction is fast,
+cheap and easy, once the material is in the hands of the customer.
+While a supplier may use SHTTP to protect the details of the
+transaction, once a print file has been sent to someone, the supplier
+retains no control whatsoever over its use, reuse and abuse. Copies
+could be sent to dozens others, or printed many times, in the space of
+minutes.
+
+\subsection{Printing from HTML}
+
+The demand for printed copies of Web material is surprisingly high.
+Although in some cases it is reminiscent of those people who insist on
+printing their email, it is undeniable that there is a serious
+requirement for good quality print from Web documents.
+
+Existing solutions to printing SGML text are usually
+application-specific, being embedded in SGML editors or DTP systems,
+but there are also some more generic packages:
+
+\begin{itemize}
+
+\item {\tt Format} by Thomas Gordon (\LaTeX)
+
+\item {\tt HTMLtoPS} by Jan K\aa rrman (PostScript)
+
+\item {\tt SGML2TeX} and {\tt WebSet} by Peter Flynn (\TeX/\LaTeX)
+
+\item {\tt SimSim} by Jonathan Fine (\TeX)
+
+\end{itemize}
+
+\noindent The use of \TeX\ systems for most of these seems to indicate
+that the similarity of markup concepts has not gone unnoticed by
+practitioners. The author's own contributions are experimental, but
+the second of them is planned as an interactive Web service, to be
+introduced in the summer of 1995. Emailing a URL to the point of
+service will cause it to be retrieved, typeset, and the output
+returned to the user by email in PostScript form. As a form of email
+browser, the control of appearance may lie in the hands of the
+user, but suggestions for how implement this are currently
+being sought\cite{ttn41}.
+
+\subsection{Problems}
+
+Implementing a professional level of typesetting from HTML raises some
+interesting questions:
+
+\begin{itemize}
+
+\item most HTML files are invalid
+
+\item most HTML authors don't understand SGML
+
+\item most HTML authors couldn't care less
+
+\item most World Wide Web users couldn't care less
+
+\end{itemize}
+
+The handling of missing, damaged or abused tags in a gracious manner
+is not a feature of most SGML parsers. At the best, a
+typesetter-browser can only be expected to report to the user that a
+file is invalid, and while it may be displayed by browsers which do
+not make any claim to typographic quality, an attempt to make a
+respectable print job of an invalid file is unlikely to succeed.
+
+\section{Development}
+
+The future of the World Wide Web and HTML is uncertain. While
+development continues, and while new users are anxious to start
+surfing the net, the existing designs and implementations will
+suffice. In the longer term, a coalescing of services is likely to
+occur, but for this to happen, a number of changes need to take place:
+
+\begin{itemize}
+
+\item The Web will start to make use of other DTDs, as outlined above.
+ Any file containing a \verb+<!doctype...>+ at the beginning could
+ cause a browser to retrieve the DTD specified, along with a style
+ sheet, and work much as any SGML-conformant DTP system would.
+
+\item Browsers will become pickier, able to offer better services at
+the expense of rejecting invalid or badly broken files. Arena already
+perfoms a form of consistency check on the HTML code of files, and
+displays `Bad HTML' in the top corner when an offender is spotted.
+
+\item Users will become pickier, demanding better response from the
+browser, better response from the server, and better facilities from
+both. As users become more educated about the use of SGML, developers
+will no longer be able to hide the deficiencies of products under the
+cover of technical detail.
+
+\item This presupposes more user education, which is inevitable in a
+developing technology. 100 years ago, motor cars appeared on the
+roads, but few passengers in them understood the use of the levers and
+rods which controlled them. With some minor exceptions, it is now
+expected that a driver knows that turning the wheel clockwise turns
+the car to the right, and {\it vice versa\/}. It will not take us that
+long to perceive the innards of HTML, but it can only be done by
+training and education.
+
+\item At some stage, investment is always needed. Many companies have
+put substantial sums into the development of Internet resources, and
+those that have done so with forethought and planning deserve to reap
+a rich reward. It is a long-term investment, more akin to a
+partnership, but support is always needed by those who undertake the
+developments, especially as much of it is done in personal time and at
+personal expense.
+
+\end{itemize}
+
+\noindent There is still some way to go before we achieve the ease of
+use of the telephone or the radio, but the path is becoming easier
+with each new development.
+
+\begin{thebibliography}{9}
+
+\bibitem{html-spec} Berners-Lee~T \& Connolly~D, {\em HyperText Markup
+Language Specification~---~2.0}, Internet Draft, IETF Working Group on
+HTML, December 1994.
+
+\bibitem{ttn41} Flynn~P, {\em Typographers' Inn}, \TeX\ and TUG NEWS,
+{\bf 4}, 1, March 1995.
+
+\bibitem{iso-sgml} Goldfarb~C, {\em The SGML Handbook}, OUP, 1990,
+ISBN 0--19--853737--9.
+
+\bibitem{krc} Kernighan~BW \& Ritchie~DM, {\em The C Programming
+Language}, Prentice-Hall, 1978.
+
+\bibitem{arena-style} Lie~H {\em et al}, {\em HTML Style sheets},
+\URL|http://www.w3.org/hypertext/WWW/Style/|
+
+\bibitem{sgml-tools} Pepper~S, {\em The Whirlwind Guide: SGML
+tools and vendors},
+\URL|ftp://ftp.ifi.uio.no/pub/SGML/SGML-Tools/SGML-Tools.txt|
+
+\end{thebibliography}
+
+\end{Article}