The Xml Companion - Softcover

Preface

The Extensible Markup Language is a powerful publishing and document interchange

format. Developed by the World Wide Web Consortium, it was released, to widespread

acclaim, in 1998. XML has a superficial resemblance to HTML, the established

language of the Web, but information held in this format is self-describing

- it can be extracted, manipulated and formatted to the requirements of any

target audience or publishing medium.

XML should be of interest to HTML designers who need more flexibility to manage

and customize their documents, to SGML users seeking advanced yet modestly priced

applications, and to software developers requiring a flexible storage or interchange

format that has powerful supporting tools.

The XML Companion serves the programmer, analyst or consultant

involved in the management, processing, transfer or publication of XML documents.

Detailed study of XML is supported by the inclusion of cross-referenced 'road

maps' of the building blocks that comprise the standard, and an extensive glossary.

Related standards for cataloguing, linking and styling XML files are also covered

in detail.

This edition
The first edition of this book was completed within weeks of the release of

the XML standard. Since that time, no significant pressure to modify or enhance

the core standard has emerged. Justification for a new edition of this book

therefore rests upon the high degree of activity surrounding XML. Complementary

standards for processing, presenting and merging XML data have since been released,

and this edition provides detailed coverage of DOM 1.0, SAX 1.0, CSS 2 and Namespaces

1.0. Other standards have progressed, but are still being refined, so this edition

simply describes later, more stable drafts of XSL (now divided into XSL and

XSLT) and XLL (now divided into XLink and XPointer). Other proposed standards

have only very recently emerged. The next version of HTML (XHTML) will be an

application of XML (instead of SGML), and the XML Catalog proposal defines a

standard scheme for managing the mapping of entity identifiers to local system

files. A new scheme for navigating around XML documents, called XPath, will

be utilised by the linking and styling standards.

This opportunity has been taken to rectify a number of minor syntactic and

grammatical mistakes, as well as a few factual errors, and thanks are due to

readers of the first edition for highlighting many of these issues.

Very little material from the first edition has been omitted, so the new book

is a little larger than before. Despite this, it is hoped that the book can

still serve as a 'companion' for those who are constantly on the move.

Acknowledgements
A repeated thanks to all those mentioned in the first edition of this book,

as their contributions remain relevant. In addition, a number of readers of

the first edition have contributed suggestions and observations that have helped

improve the quality of this work, and their efforts are appreciated. Finally,

thanks once again to Adobe for FrameMaker+SGML (which was used both in the preparation

and publication of this book).

Feedback
Comments and suggestions for a possible future edition are welcome. They should

be sent to the author, who can be found at neil@bradley.co.uk.

Updates, additions and corrections can be obtained from the author's Web page,

located at 'bradley.co.uk',

which also contains links to various XML and SGML related sites.

Neil Bradley
August1999 0201674866P04062001

Neil Bradley is an XML consultant with almost twenty years' practical experience in the field of mark-up languages. He is an experienced trainer, a regular speaker at industry events and contributes to specialist magazines and journals.