Resource Description Framework (RDF)
The Resource Description Framework (RDF) integrates a
variety of applications from library
catalogs and world-wide directories to syndication and aggregation of news, software, and
content to personal collections of music,
photos, and events using XML as an
interchange syntax. The RDF specifications
provide a lightweight ontology system to support the exchange
of knowledge on the Web.
The W3C Semantic Web Activity
Statement explains W3C's plans for RDF, including the RDF Core WG, Web Ontology and the RDF Interest Group.
The RDF suite of specifications consist of:
The RDF Specifications depend on URI and XML
technologies.
Other relevant
W3C technical reports include:
- An
RDF Schema for P3P
W3C Note 25 January 2002, Brian McBride, Rigo Wenning,
Lorrie Cranor
- An RDF Schema for
the XML Information Set
W3C Note 06 April 2001, Richard Tobin
- Composite
Capability/Preference Profiles (CC/PP): Structure and
Vocabularies
W3C Working Draft 15 March 2001, Graham Klyne, Franklin
Reynolds, Chris Woodrow, Hidetaka Ohto
- Harvesting RDF
Statements from XLinks
W3C Note 29 September 2000, Ron Daniel Jr.
- Accessibility
Features of SVG
W3C Note 7 Aug 2000. Charles McCathieNevile, Marja-Riitta
Koivunen
discussion Sep 2000. implements an SVG-to-text
convertor.
- PICS Rating
Vocabularies in XML/RDF
W3C NOTE 27 March 2000
- Cambridge
Communiqué
W3C NOTE Oct 1999 on application schema layering
- Web Architecture:
Describing and Exchanging Data
Berners-Lee, Connolly, Swick, W3C Note 7 June 1999
- Document
Content Description for XML
submitted July 1998 to the W3C by IBM and Microsoft. DCD is
an RDF vocabulary to define document constraints in an XML
syntax.
- W3C Data
Formats
W3C NOTE 29-October-1997, Tim Berners-Lee
See also Tim Berners-Lee's writings on Web Design Issues
including Metadata
Architecture.
These sites track
developments related to RDF:
While the RDF specs provide the most
in-depth details about RDF, a number of shorter overviews and
presentations are also available, for developers and for a
general audience.
- RDF
and Metadata, Tim Bray, June 09, 1998, xml.com
- Getting into RDF &
Semantic Web using N3, Tim Berners-Lee
- Peer-to-Peer and the Semantic Web:
The Power of Metadata, book chapter by Rael Dornfest
& Dan Brickley
- An
Idiot's Guide to the Resource Description Framework by
Renato Iannella, January 25, 1999.
- RDF
tutorial, Pierre-Antoine Champin (for
developers)
- Summary
of RDF API Discussions (for developers)
- Web
Metadata: A Matter of Semantics by Ora Lassila, IEEE
Internet Computing, July-August 1998
- An
Introduction to the Resource Description Framework by
Eric Miller, D-Lib Magazine, May 1998
- Putting
RDF to Work, Edd
Dumbill.
- Distributed
XML: the role played by XML in the next-generation Web,
Edd
Dumbill.
- XML and
the Web, by Tim
Berners-Lee, XML World 2000, Boston 2000/09/06
- Frequently asked questions(FAQ) about
RDF, with answers.
-
DAML could take search to a new level, Jim Rapoza, PC
Week Labs February 7, 2000
- A New
Dawn, Glyn Moody, New Scientist, May 30, 1998
- Getting
Deep Into Metadata, Nate Zelnick, The XML Files, a
WebDeveloper.com Feature, June 12, 1998
See also W3C in The Press,
e.g. New
Specs Are In the Works for Web Data, Brian Hannon, PC Week,
May 29, 1998 and
Resource Description Framework Press in the RDF Resource Guide
RDF is an enabling technology for a wide variety of
projects. The following is a sample; the
Resource Description Framework Applications and Projects
section in the RDF Resource Guide
lists many more.
-
Dublin Core Metadata
Initiative
The Dublin Core Metadata Initiative is an open forum
engaged in the development of interoperable online
metadata standards that support a broad range of purposes
and business models. DCMI's activities include
consensus-driven working groups, global workshops,
conferences, standards liaison, and educational efforts
to promote widespread acceptance of metadata standards
and practices.
-
Open Directory Project
The Open Directory Project is the largest, most
comprehensive human-edited directory of the Web. It is
constructed and maintained by a vast, global community of
volunteer editors.
Copyright (c) 1998-2001 Netscape Free Use
License
RDF dumps of the
are available. Note: these dumps don't
quite conform to the final RDF specification but rather to
an earlier working draft. See:
- xmlTree - an index
of XML content providers. The index is served in both RDF
form and presented for human readability.
-
DSpace
a digital archive created to capture and distribute the
intellectual output of MIT.
The dspace component
of Semantic Web Advanced
Development aims to survey existing RDF data stores and
examine effective techniques for storing complex metadata
in a variety of systems.
While content rating was
the application that originally motivated the developoment of
PICS and RDF, syndication and
aggregation have emerged as cost-effective applications of
RDF.
-
lightweight multipurpose extensible metadata description
and syndication format.
proposed Aug 2000 to the RDF Interest Group
- XMLNews-Meta - A
suite of specifications for exchanging news and information
using open Web standards
-
PRISM: Publishing
Requirements for Industry Standard Metadata
PRISM is a packaging and metadata format, similar to
NewsML, RSS, and XMLNews-Meta. Like RSS 1.0 and
XMLNews-Meta (but not NewsML), PRISM is based on RDF. PRISM
is developed by an industry consortium of publishing
software developers and publishers, including (among many
others) Adobe, Quark, Condé Nast, and Time Inc.
- The UK Mirror Service is a
national UK service providing mirrors/collections of software
and data from around the world. It uses RDF
internally for mirror description and mirror content
description of over 4 million resources. April 2000
- Daniel Veillard's Linux Packages
Database, a tool that makes use of RDF encoded metadata
for locating and identifying dependencies between software
packages available for the Linux operating system.
-
Java, RDF, and the "Virtual Web", Leon Shklar (see also
parts
two and
three), a Gamelan Tech Focus series on content
syndication and aggregation strategies, September/October
1999.
Some of the most exciting applications of RDF are at a
smaller scale, very close to home. These applications depend on
emerging technical and social mechanisms for managing trust on
the web (access control, privacy, rights management), so as of
this writing (Aug 2001) they tend to be advanced development projects more
than production systems.
The major resource for RDF development activity is the W3C RDF Interest Group mailing list (archives)
and its IRC
chat channel (logs) with
its blog scratchpad (RSS 1.0 news
feed)
A good introduction for developers is What is
RDF? by Tim Bray
on XML.com who have a growing
series of articles and reports about RDF applications including
Putting
RDF to Work, RDF
Calendar taskforce,
RDF with prolog, RDF -
why we should care - and RSS, Building
the Semantic Web,
The Semantic Web: A Primer and many others.
Developer news
Java Developers
- The Jena Java RDF
API and toolkit is a comprehensive Java system by Brian
McBride, Jeremy Carroll, Andy Seaborne, Dave Reynolds and
Ian Dickinson, HP
Labs, Bristol. Jena contains an API for manipulating RDF
models including statement and resource-centric methods using
cascading calls for easy object orientated use, container
support, the ARP RDF/XML parser, an RDF/XML writer, the RDQL
query language, DAML support, persistent storage. Available
under an open source, BSD-like license. See the jena discussion
list for more information.
- The ICS-FORTH
RDFSuite which are designed to provide open source,
high-level scalable tools for the Semantic Web. This suite
includes VAalidating RDF Parser (VRP),
a RDF Schema Specific
DataBase (RSSDB) and supporting RDF Query Language
(RQL)
- IsaViz: A visual authoring
tool for browsing and authoring RDF models represented as
graphs. Developed by Emmanuel Pietriga of W3C and Xerox Research Centre
Europe, IsaViz is based on the Xerox
Visual Transformation Machine.
Perl Developers
Python Developers
- The Redfoot RDF
framework by James
Tauber and Dan Krech
provides a system for building distributed data-driven web
applications with RDF and Python. It includes an RDF
database, query API, template language, module architecture,
editor all with web interface, sample applications and the
beginnings of P2P support. Available under a BSD-style
License.
- The W3C Semantic Web Area for
Play by Tim Berners-Lee and Dan Connolly contains lots of
small Python tools for RDF and beyond-RDF research tools
including the Closed World
Machine (CWM) data manipulator, rules processor and query
system mostly using using the Notation 3 textual
RDF syntax. Available under W3C open source license.
- The 4Suite 4RDF Python
library provides open source tools for manipulating and
querying RDF data, including inference capabilities. The
xml.com article, 4RDF:
A Library for Web Metadata includes an overview of the
system with worked examples.
C developers
Tcl/Tk developers
Conceptual Graphs
SOAP/WSDL
UML/MOF/XMI
- Representing
UML in RDF The goal of this work is to make UML
"RDF-compatible". This allows mixing and extending UML models
and the language elements of UML itself on the Web in an open
manner.A
testbed converter that supports automatic translation
from UML/XMI to RDFS/RDF/XML.
- A
Layered Approach to Information Modeling and Interoperability
on the Web Sergey Melnik, Stefan Decker, Database Group,
Stanford University, : Sep 4, 2000
- A Discussion
of the Relationship Between RDF-Schema and UML, Walter W.
Chang, Advanced Technology Group, Adobe Systems, W3C Note,
04-Aug-1998
-
Networked Knowledge Representation and Exchange using UML and
RDF Stephen Cranefield, Journal of Digital Information,
volume 1 issue 8, 2001-02-15
- DAML/UML Based
Ontology Set from Lockheed Martin
TopicMaps
- XML
Topic Maps through RDF Glasses, Presented at KT2001, Nikita Ogievetsky,
Cogitech, Inc.
- DAML and Quantum
Topic Maps, Presented at KT2002, Nikita Ogievetsky,
Cogitech, Inc.
- XTM to RDF
converter, Cogitech, Inc.
- Representing XML
Topic Maps as RDF, Eric van der Vlist.
- RDF
and Topic Maps: An Exercise in Convergence, Graham
Moore.
-
On the integration of Topic Maps and RDF, Martin
Lacher.
-
Topic maps, RDF, DAML, OIL. A comparison, Lars Marius
Garshol.
Events and publications in the history of RDF include...
- May 2001: WWW10 W3C's
Semantic Web Track and the Semantic Web
Developers Day. Hong Kong
- Feb 2001: RDF Interest Group meeting
(26-27 Feb 2001)
- Feb 2001: Semantic
Web Activity launched
- Oct 1999: "Cambridge
Communiqué" W3C NOTE issued on application schema
layering
- Sep 2000 XML World 2000 talk: XML and the Web, by Tim Berners-Lee.
- Mar 2000: RDF Schema
Specification 1.0 published as a W3C Candidate
Recommendation (
call for implementation)
- Aug 1999: RDF
Interest Group created
- Feb 1999: RDF Model
and Syntax Specification released as a W3C
Recommendation (press
release)
- May 1998 RDF - Using XML to describe
Data, Swick, WWW8 presentation
- April 1998 WWW7 Tutorial, Using
Web Metadata: Dublin Core and the Resource Description
Framework, Lagoze, Miller, Lassila, Swick, Iannella,
Schloss, Weibel
- Dec 1997 W3C Metadata Activity Statement
presented to the W3C Membership
- Nov 1997 Introduction
to RDF Metadata, W3C NOTE 1997-11-13, Ora Lassila
- Oct 1997 first RDF working draft
released