1. file: xmlintro.ppt, 6/4/2016, version 1.0 “What is XML?” Metadata Registries Workshop II April 15, 1998 Page 1 of 20 What is XML (and RDF)? John McCarthy & Frank Olken jlmccarthy@lbl.gov olken@lbl.gov Lawrence Berkeley National Laboratory Roy Tennant rtennant@library.berkeley.edu The Library, University of California, Berkeley http://www.lbl.gov/~olken/epa.html Metadata Registries Workshop II Washington, DC 15 April 1998

2. file: xmlintro.ppt, 6/4/2016, version 1.0 “What is XML?” Metadata Registries Workshop II April 15, 1998 Page 2 of 20 XML: Extensible Markup Language u World Wide Web Consortium (W3C) Recommendation, Version 1.0 February 1998 u Simplified SGML (Standard Generalized Markup Language, ISO 1986) u adopts UNICODE international character set u Next generation HTML: u semantic structure of document or data u extensible, industry-specific tag sets u display determined by stylesheets (CSS, XSL)

3. file: xmlintro.ppt, 6/4/2016, version 1.0 “What is XML?” Metadata Registries Workshop II April 15, 1998 Page 3 of 20 A Simple XML Example Richard Light rlight@somewhere.com Presenting XML Markup Character Data

4. file: xmlintro.ppt, 6/4/2016, version 1.0 “What is XML?” Metadata Registries Workshop II April 15, 1998 Page 4 of 20 Goals & Philosophy of XML u Overcomes shortcomings of HTML: u allows processing of Web documents by sophisticated document processing software u Overcomes shortcomings of SGML: u allows media-independent electronic publishing u Interoperates with SGML and HTML u Provides vendor-neutral data exchange

5. file: xmlintro.ppt, 6/4/2016, version 1.0 “What is XML?” Metadata Registries Workshop II April 15, 1998 Page 5 of 20 XML History u Roots in SGML u very extensible but very complicated u a simplified SGML could greatly expand the power and flexibility of the Web u XML proposal to W3C in July 1996 u John Bosak, Sun Microsystems, now XML Chair u First XML Meeting, August 1996, Seattle

6. file: xmlintro.ppt, 6/4/2016, version 1.0 “What is XML?” Metadata Registries Workshop II April 15, 1998 Page 6 of 20 XML Family of Standards u XML (W3C Proposal, Version 1.0 February 1998) u simplified SGML (ISO 8879:1986) u Extensible Stylesheet Language (XSL) u based on DSSSL (stylesheet specification ISO/IEC 10179, used for SGML) u XML Linking Language (XLink) u based on HyTime (ISO/IEC 10744:1992) u provides rich linking mechanisms (e.g., multidirectional links)

7. file: xmlintro.ppt, 6/4/2016, version 1.0 “What is XML?” Metadata Registries Workshop II April 15, 1998 Page 7 of 20 What is W3C? u World Wide Web Consortium (www.w3.org) u Tim Berners-Lee, Director u Staff at MIT, US; INRIA, France; Keio Univ., Japan u Over 220 member organizations (April 1998) u for profit > $50,000,000 pay $50,000/year u other for profit, gov’t, and non profit pay $5,000/year u Fast track Web standards development u Short-term, specific focus Working Groups

8. file: xmlintro.ppt, 6/4/2016, version 1.0 “What is XML?” Metadata Registries Workshop II April 15, 1998 Page 8 of 20 Current W3C Development Areas u Architecture u HTTP-NG, etc. u User Interface u HTML, CSS, XSL, etc. u Privacy and Site Rating u P3P, PICS, etc. u Data Exchange u XML, RDF, etc.

9. file: xmlintro.ppt, 6/4/2016, version 1.0 “What is XML?” Metadata Registries Workshop II April 15, 1998 Page 9 of 20 XML Bandwagon u Major support from vendors: u Microsoft, Sun, Netscape,... u High-end technical publishers (SGML) u Conferences: u SGML/XML, November 1997, Wash. DC u XML Conference, March 1998, Seattle u SGML/XML, May 1998, Paris u XML World, September 1998, Ottawa u Books, Software, Web sites, Articles

10. file: xmlintro.ppt, 6/4/2016, version 1.0 “What is XML?” Metadata Registries Workshop II April 15, 1998 Page 10 of 20 XML Software Tools u XML-enabled Web browsers u e.g., Microsoft Internet Explorer, Netscape u XML parsers u e.g., http://www.microsoft.com/xml/ u XML stylesheet editing software u e.g., http://www.arbortext.com/xmlstyler/ u CDF (Channel Definition Framework) u e.g., http://www.microsoft.com/standards/cdf.htm u Software for structured text u Survey: http://www.cs.uku.fi/~kuikka/systems.html u Pointers: http://www.sil.org/sgml/publicSW.html u SoftQuad (www.sq.com), Arbortext (www.arbortext.com)

11. file: xmlintro.ppt, 6/4/2016, version 1.0 “What is XML?” Metadata Registries Workshop II April 15, 1998 Page 11 of 20 Discipline-Specific Proposals u Chemical Markup Language (ChemML) u Math Markup Language (MathML) u Electronic Document Interchange (XML-EDI) u Bioinformatic Sequence Markup Language (BSML) u Synchronized Multimedia Integration Language (SMIL) u Web Interface Definition Language (WIDL) u Precision Graphics Markup Language (PGML) u Information and Content Exchange (ICE) u Tutorial Markup Language (TML) u Open Software Description Format (OSD)

12. file: xmlintro.ppt, 6/4/2016, version 1.0 “What is XML?” Metadata Registries Workshop II April 15, 1998 Page 12 of 20 XML and EDI u XML-EDI Group within Graphic Communications Association u XML-EDI being examined in X12 u CommerceNet Industry Initiative u creating tag sets for EDI u Telecommunications Interchange Markup (TCIF/IPI) u More information: u http://www.xmledi.org/ (http://www.geocities.com/WallStreet/Floor/5815/)

13. file: xmlintro.ppt, 6/4/2016, version 1.0 “What is XML?” Metadata Registries Workshop II April 15, 1998 Page 13 of 20 General Proposals u W3C Document Object Model (DOM) u enables script access to document components u Channel Definition Format (CDF) u specifications for push content u XML-Data (Note from Microsoft) u XML encoding for DTDs and data types u Resource Description Framework (RDF) u metamodel for Web metadata

14. file: xmlintro.ppt, 6/4/2016, version 1.0 “What is XML?” Metadata Registries Workshop II April 15, 1998 Page 14 of 20 Resource Description Framework u Interoperability for applications that use metadata u Enables industry-specific groups to independently define, maintain, and reuse vocabularies (schemas) u Architecture includes: u Graph data model (like NIAM, AI frames) u Transfer syntax (XML) for interchange u Human-readable and machine-parseable syntax u RDF Working Groups (http : //www.w3.org/RDF/) u model and syntax u schema

15. file: xmlintro.ppt, 6/4/2016, version 1.0 “What is XML?” Metadata Registries Workshop II April 15, 1998 Page 15 of 20 RDF Architecture XML replaces SGML and allows the expression of structure; RDF allows the expression of semantics. - Tim Berners-Lee

16. file: xmlintro.ppt, 6/4/2016, version 1.0 “What is XML?” Metadata Registries Workshop II April 15, 1998 Page 16 of 20 XML, Metadata & Registries u Encode metadata in XML (and RDF) u Use Registries to manage tag sets u For self-describing data and metadata exchange (transmission format) u Links to reference metadata registries u Use XML/RDF for registry schemas (metamodels)

17. file: xmlintro.ppt, 6/4/2016, version 1.0 “What is XML?” Metadata Registries Workshop II April 15, 1998 Page 17 of 20 W3C Namespaces Proposals u Naming Contexts (e.g., ISO 11179) u Divide and conquer name collisions u Library of Congress means book title: From Here to Eternity u Department of Commerce means job title: Chief Bottle Washer u W3X document on XML Namespaces u http://www.w3.org/TR/WD-xml-names

18. file: xmlintro.ppt, 6/4/2016, version 1.0 “What is XML?” Metadata Registries Workshop II April 15, 1998 Page 18 of 20 Mixing & Matching Namespaces Layman Andrew The Call of the Wild London, Jack

19. file: xmlintro.ppt, 6/4/2016, version 1.0 “What is XML?” Metadata Registries Workshop II April 15, 1998 Page 19 of 20 Where XML is Going u Increasing industry interest and acceptance u Parsers in multiple computer languages: u Java, C++, Perl, Python, etc. u Additional industry-specific tag sets u Full Web browser support u Growing set of authoring/processing tools

20. file: xmlintro.ppt, 6/4/2016, version 1.0 “What is XML?” Metadata Registries Workshop II April 15, 1998 Page 20 of 20 XML Resources u Standards proposals: http://www.w3.org/XML/ u Web Sites: u Robin Cover: http://www.sil.org/sgml/xml.html u Seybold/O’Reilly: http://xml.com/ u Web Review: http://webreview.com/xml/ u Electronic Discussions: u XML-L: LISTSERV@listserv.hea.ie u XML-Dev: http://www.lists.ic.ac.uk/hypermail/xml-dev/ u Documents: u FAQ: http://www.ucc.ie/xml/ u BYTE article: http://www.byte.com/art/9803/sec5/sec5.htm