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+\def\latextohtml{\LaTeX{2}{\tt{HTML}} }
+\def\htmladdnormallink#1#2{ #1\footnote{#2}}
+\def\bull{$\bullet $ }
+
+% MYFIG
+% #1 - name without the .ps extension
+% #2 - caption
+% Frames the picture.
+\newcommand{\myfig}[2]
+ {\begin{figure*}
+ \centerline{%
+ \epsfig{file=#1.ps,height=.9\textheight}}
+ \caption{#2}
+ \label{fig:#1}
+ \end{figure*}}
+
+
+\title{Text to Hypertext Conversion with \latextohtml}
+\author[Nikos Drakos]{Nikos Drakos,\\ Computer Based Learning Unit,\\
+University of Leeds, Leeds LS2 9JT, UK.\\
+email: {\tt nikos@cbl.leeds.ac.uk}\\
+www: {\tt http://cbl.leeds.ac.uk/nikos/personal.html}\\
+}
+
+\begin{article}
+\begin{abstract}
+\latextohtml is a conversion tool that allows existing documents
+written in \LaTeX\ to become part of a global multimedia system.
+This paper presents some of the reasons for using such a system and
+describes the basic conversion process.
+\end{abstract}
+
+\section{World Wide Web --- A Global Multimedia System}
+\begin{quotation}
+Imagine a system that links all the text, data, digital sounds,
+graphics and video on all the world's computers into a single
+interlinked hypermedia ``web''. This is the potential of the
+Internet-based
+World Wide Web (WWW or W3) project \ldots \cite{levy:www}
+\end{quotation}
+
+The World Wide Web merges hypermedia techniques with networked
+document retrieval to provide a global information system of linked
+documents. These are traversed by ``clicking'' in textual or iconic
+active areas, or searched via query mechanisms \cite{tbl:www}. Hypertext links
+may point to a different location in the same document or to another
+document which may be located perhaps in another continent!
+
+Documents are not limited to containing only textual information
+and may include high resolution images, audio and video samples.
+WWW also encompasses most of the services currently available on the
+Internet such as Usenet news, ftp, wais, archie, etc. Access
+to these services as well as the invocation of arbitrary computer
+programs (e.g.\ a database access or a simulation) is completely
+transparent to the user who sees them all
+as part of some document and interacts with them in a uniform
+and intuitive way.
+
+Multimedia documents are written in a language designed specifically
+for the World Wide Web called HTML (HyperText Markup Language) which
+is based on SGML (Structured Generalised Markup Language). Documents
+are written by information providers who just place them on the WWW
+using a ``server'' program. Then anyone with access to the Internet
+can use a ``client'' or ``browser'' program to access and view
+available documents. Clients and servers communicate via the HTTP
+protocol (HyperText Transfer Protocol). Apart from navigation
+facilities, browsers also allow full text searches, ``cut and paste'',
+text or audio annotations, personal ``hotlists'', saving and printing
+in multiple formats and others. Such browser and server programs are
+freely available for most popular computer configurations.
+
+With the explosive growth of the World Wide Web (500-fold since the
+first graphical browsers were made available this year \cite{vern:www}), and a
+potential audience of 15 million in more than 50 countries, providing
+information via the WWW is becoming an extremely attractive proposition.
+
+\section{\LaTeX\ to HTML Conversion: Why?}
+
+HTML is quite a simple markup language to learn and use. It allows basic
+formatting commands, bulleted lists, ``inlined'' images, and hypertext
+links to other documents, multimedia sources, internet services or
+computer programs. But despite (and
+because of) its simplicity it has created a few headaches for
+information providers:
+
+\begin{itemize}
+\item there are no intuitive authoring tools (yet);
+\item yet another hypertext language has to be learned;
+\item existing documents available in other formats have to be reprocessed;
+\item hypertext document ``webs'' are difficult to maintain;
+\item it is difficult or impossible to create highly formatted
+documents in HTML.
+\end{itemize}
+
+\latextohtml can be used in order to address to a large degree these
+problems. The authoring problem simply disappears, existing documents
+can be reused immediately and a complex web of interlinked documents
+can be generated from a single source document. The automatic
+inclusion of formatted information such as tables or mathematical
+equations as inlined images also bypasses another serious problem with
+HTML. An additional benefit is that the paper-based version of a
+document can also be obtained from the same source.
+
+The utility of a conversion tool like \latextohtml can be seen from
+the variety of contexts in which it has been applied. Some examples
+are listed below.
+\begin{itemize}
+\item Electronic books (e.g.\ that produced by the Computational
+ Science Education
+ Project\footnote{http://compsci.cas.vanderbilt.edu/csep.html} which
+ is sponsored by the US Department of Energy. This is one of the most
+ complex documents currently available via the WWW.).
+\item General reports (e.g.\ the annual report of the Institute of
+ Astronomy at Cambridge\footnote{
+ http://cast0.ast.cam.ac.uk/sub\-$\_$dir/cambridge/annual\-$\_$report/annual$\_$report.html}).
+\item User
+manuals\footnote{http://cs.indiana.edu:80/elisp/w3/docs.html}.
+\item System
+ documentation\footnote{http://archie.ac.il:8001/papers/papers.html}.
+\item Scientific papers such as those on the MIT Transit
+ Project\footnote{http://www.ai.mit.edu/projects/transit/tn-cat.html}.
+\item Electronic journals (e.g.\ Complexity
+ International\footnote{http://life.anu.edu.au/ci/ci.html} --- a new
+ Australian electronic journal).
+\end{itemize}
+\section{\LaTeX\ to HTML conversion: How?}
+The basic conversion process relies on the ability to distinguish
+between the {\em structure}, the {\em content} and the {\em
+formatting} information in a \LaTeX\ document.
+
+On the basis of sectioning information, a document is broken into
+separate parts and an iconic navigation mechanism is constructed in
+HTML which reflects this structure and allows a user to ``jump''
+between different parts. The cross-references, citations, footnotes,
+the table of contents and the lists of figures and tables are also
+translated into hypertext links. Formatting information which has
+equivalent ``tags'' in HTML (lists, quotes, paragraph breaks, type
+styles, etc.) is also converted appropriately.
+
+Although in most cases the loss of some formatting information (e.g.
+page margins or line widths) is harmless, there are occasions where
+the format has meaning e.g.\ when dealing with tables or user defined
+environments. Another problem is the replication of the mathematical
+equations which must retain both their precise format as well as any
+of the predefined special mathematical symbols.
+
+The innovative solution in such cases relies on the ability of HTML
+browsers to display inlined images inside the main text. Any part of a
+\LaTeX\ document for which it is not obvious how it should be
+translated directly into HTML is extracted from the main document and
+then placed on a pipeline which converts it into an image. Each image
+is then placed at the correct position in the final HTML document.
+Special care is taken to preserve contextual information that may
+affect the contents of each image (counter values, labels, references,
+active style files etc). Some examples of converted documents can be
+seen in Figure \ref{fig:mosaic}.
+
+\myfig{mosaic}{A converted document displayed using Mosaic}
+
+
+\section{Hypermedia Extensions to \LaTeX}
+Apart from the obvious hypertext links within a \LaTeX\ document (e.g.
+navigation between sections, cross-references and citations) it is
+also possible to take full advantage of the HTML links to arbitrary
+multimedia sources (e.g.\ audio or video), electronic forms, and other
+remote documents or internet services.
+
+This can be done with some new commands defined in a separate style
+file ({\tt html.sty}) which are processed in a special way by the
+\latextohtml translator. This style file defines commands for
+embedding external hypertext links, for extending the basic {\tt
+ \verb#\#ref-\verb#\#label} mechanism to operate between remote
+documents, and specifying that some text should only appear in the
+paper-based version or only in the HTML document. In most cases these
+commands have no effect when processed in the conventional way.
+
+Another command allows the inclusion of arbitrary HTML markup
+directly in a \LaTeX\ document. This can be used to take advantage
+of new HTML facilities as soon as they become available (HTML is
+currently evolving towards a new specification called HTML+).
+A particularly
+good use of this feature is in the creation of interactive
+electronic forms from within a \LaTeX\ document.
+
+\section{Concluding Remarks}
+Conversion tools like \latextohtml provide an easy migration path
+from familiar concepts towards authoring complex and format-rich
+hypermedia documents. In this way, familiarity with a system
+like \LaTeX\ makes it possible to contribute to and benefit from
+a rapidly expanding global hypermedia network.
+
+\bibliographystyle{plain}
+\begin{thebibliography}{1}
+
+\bibitem{tbl:www}
+T.~Berners-Lee, R.~Cailliau, J.~Groff, and B.~Pollerman.
+\newblock Worldwide web: The information universe.
+\newblock {\em Electronic Networking: Research, Application and Policy}, (1),
+ 1992.
+
+\bibitem{levy:www}
+Joe Levy.
+\newblock The world in a web.
+\newblock {\em {\it The} Guardian}, page~19, November 11 1993.
+
+\bibitem{vern:www}
+Vern Paxson.
+\newblock Growth trends in wide-area {TCP} connections.
+\newblock {\em IEEE Network}, To Appear 1993.
+\newblock Available at ftp://ftp.ee.lbl.gov/WAN-TCP-growth-trends.revised.ps.Z.
+
+\end{thebibliography}
+
+\appendix
+
+\section{Further Information}
+\latextohtml is written in Perl and requires freely available
+software. \htmladdnormallink{More information on how to get, install
+ and use it is available via the
+ WWW}{http://cbl.leeds.ac.uk/nikos/\-tex2html/doc/latex2html/\-latex2html.html}
+or using anonymous ftp from ftp.tex.ac.uk in
+pub/archive/support/latex2html. A new release is planned for early
+December 1993.
+
+Several computers on the Internet have public access World Wide Web
+clients accessible by telnet e.g.\ \\ \bull telnet info.cern.ch (direct
+connection --- no username or password required) \\ \bull telnet
+ukanaix.cc.ukans.edu (``Lynx'' requires a vt100 terminal. Log in as
+www.)
+
+Information on World Wide Web is also available via anonymous ftp from
+{\tt ftp.germany.eu.net} in {\tt pub/infosystems/www}. The Mosaic clients are
+in the directory {\tt /pub/infosystems/www/ncsa/Web}.
+
+\end{article}
+
+
+