RDF and OWL Become W3C Recommendations

World Wide Web Consortium Issues RDF and OWL Recommendations

Semantic Web Emerges as Commercial-Grade Infrastructure for Sharing Data on the Web

http://www.w3.org -- 10 February 2004.

Today, the World Wide Web Consortium announced final approval of two key Semantic Web technologies, the revised Resource Description Framework (RDF) and the Web Ontology Language (OWL). RDF and OWL are Semantic Web standards that provide a framework for asset management, enterprise integration and the sharing and reuse of data on the Web. These standard formats for data sharing span application, enterprise, and community boundaries - all of these different types of "user" can share the same information, even if they don't share the same software.

Today's announcement marks the emergence of the Semantic Web as a broad-based, commercial-grade platform for data on the Web. The deployment of these standards in commercial products and services signals the transition of Semantic Web technology from what was largely a research and advanced development project over the last five years, to more practical technology deployed in mass market tools that enables more flexible access to structured data on the Web. Testimonials from enterprise-scale implementors and independent developers illustrate current uses of these standards on the Web today.

"RDF and OWL make a strong foundation for Semantic Web applications," said Tim Berners-Lee, W3C Director and inventor of the World Wide Web. "Their approval as W3C Recommendations come at a time when new products spring up in areas as diverse as Enterprise Integration and medical decision support. It's not unlike the early days of the Web, when once people saw how it worked, they understood its power. We're entering that phase now, where people can see the beginnings of the Semantic Web at work."

A World Wide Web Consortium (W3C) Recommendation is understood by industry and the Web community at large as a Web standard. Each Recommendation is a stable specification developed by a W3C Working Group and reviewed by the W3C Membership. Recommendations promote interoperability of Web technologies of the Web by explicitly conveying the industry consensus formed by the Working Group.

Wide Range of Applications Growing from New Semantic Web Standards

Semantic Web-enabled software using RDF and OWL include:

Content creation applications: Authors can connect metadata (subject, creator, location, language, copyright status, or any other terms) with documents, making the new enhanced documents searchable
Tools for Web site management: Large Web sites can be managed dynamically according to content categories customized for the site managers
Software that takes advantage of both RDF and OWL: Organizations can integrate enterprise applications, publishing and subscriptions using flexible models
Cross-application data reuse: RDF and OWL formats are standard, not proprietary, allowing data reuse from diverse sources

Many specific examples of commercial applications and enterprise scale implementations of these technologies are detailed in both the testimonial page, and the RDF Implementations and OWL Implementations pages.

How the Semantic Web Pieces Fit Together -- XML, RDF and OWL

Much has been written about the Semantic Web, as if it is a replacement technology for the Web we know today. "In reality," countered Eric Miller, W3C Semantic Web Activity Lead, "it's more Web Evolution than Revolution. The Semantic Web is made through incremental changes, by bringing machine-readable descriptions to the data and documents already on the Web. XML, RDF and OWL enable the Web to be a global infrastructure for sharing both documents and data, which make searching and reusing information easier and more reliable as well."

W3C's Semantic Web Activity builds on work done in other W3C Activities, such as the XML Activity. Its focus is to develop standard technologies, on top of XML, that support the growth of the Semantic Web.

XML Provides Rules, Syntax for Structured Documents

At the foundation, XML provides a set of rules for creating vocabularies that can bring structure to both documents and data on the Web. XML gives clear rules for syntax; XML Schemas then serve as a method for composing XML vocabularies. XML is a powerful, flexible surface syntax for structured documents, but imposes no semantic constraints on the meaning of these documents.

RDF Delivers a Data Framework for the Web

RDF -- the Resource Description Framework -- is a standard a way for simple descriptions to be made. What XML is for syntax, RDF is for semantics: a clear set of rules for providing simple descriptive information. RDF Schema then provides a way for those descriptions to be combined into a single vocabulary. RDF is integrated into a variety of applications including:

library catalogs
world-wide directories
syndication and aggregation of news, software, and content
personal collections of music, photos, and events

In these cases, each uses XML as an interchange syntax. The RDF specifications provide a powerful framework for supporting the exchange of knowledge on the Web.

"RDF is part of the foundation of a major advance in the power of the Web. Ultimately, we will see users and applications combining information represented in RDF from multiple sources on the Web in ways that, until now, have been inconceivable," explains Brian McBride, Chair of the RDF Core Working Group, "The RDFCore Working Group has turned the RDF specifications into both a practical and mathematically precise foundation on which OWL and the rest of the Semantic Web can be built."

OWL Delivers Ontologies that Work on the Web

What's needed next is a way to develop subject -- or domain -- specific vocabularies. That is the role of an ontology. An ontology defines the terms used to describe and represent an area of knowledge. Ontologies are used by people, databases, and applications that need to share subject-specific (domain) information -- like medicine, tool manufacturing, real estate, automobile repair, financial management, etc. Ontologies include computer-usable definitions of basic concepts in the domain and the relationships among them. They encode knowledge in a domain and also knowledge that spans domains. In this way, they make that knowledge reusable.

OWL -- the Web Ontology Language -- provides a language for defining structured, Web-based ontologies which delivers richer integration and interoperability of data among descriptive communities. Where earlier languages have been used to develop tools and ontologies for specific user communities (particularly in the sciences and in company-specific e-commerce applications), they were not defined to be compatible with the architecture of the World Wide Web in general, and the Semantic Web in particular.

OWL uses both URIs for naming and the description framework for the Web provided by RDF to add the following capabilities to ontologies:

Ability to be distributed across many systems
Scalability to Web needs
Compatibility with Web standards for accessibility and internationalization
Openness and extensibility

OWL builds on RDF and RDF Schema and adds more vocabulary for describing properties and classes: among others, relations between classes (e.g., disjointness), cardinality (e.g., "exactly one"), equality, richer typing of properties, characteristics of properties (e.g., symmetry), and enumerated classes.

"OWL takes a major step forward in representing and organizing knowledge on the World Wide Web. It strikes a sound balance between the needs of industry participants for a language which addresses their current Web use cases, and the restrictions on developing an ontology language that meshed with established scientific principles and research experience," explained Jim Hendler and Guus Schreiber, co-chairs for the Web Ontology Working Group. "Over fifty Working Group members have successfully designed a language that addresses both sets of concerns and is endorsed by academics and practitioners alike."

RDF and OWL Documents Include Primers, Use Cases, Test Suites, to Aid Developers

The W3C RDF Core Group has produced six documents. Each is aimed at different segments of those wishing to learn, use, implement or understand RDF. The RDF Primer is an introduction to, and tutorial on how to use, RDF and RDF Schema. RDF Concepts and Abstract Syntax specifies the fundamental concepts and information model of RDF. The RDF/XML Syntax Specification (Revised) defines how to write RDF in XML syntax. RDF Vocabulary Description Language 1.0: RDF Schema describes how to use RDF to describe application and domain specific vocabularies. RDF Semantics defines the mathematically precise formal semantics of RDF and RDF Schema. RDF Test Cases defines a set of test cases that illustrate aspects of the other specifications and may be used for the automatic testing of implementations.

The W3C Web Ontology Working Group has produced six OWL documents. Each is aimed at different segments of those wishing to learn, use, implement or understand the OWL language. Documents include:

a presentation of the use cases and requirements that motivated OWL
an overview document which briefly explains the features of OWL and how they can be used
a comprehensive Guide that walks through the features of OWL with many examples of the use of OWL features
a reference document that provides the details of every OWL feature
a test case document, and test suite, providing over a hundred tests that can be used for making sure that OWL implementations are consistent with the language design
a document presenting the semantics of OWL and details of the mapping from OWL to RDF

Industrial and Academic Leaders Move Semantic Web Standards Forward

The RDF Core Working Group is comprised of industrial and academic expertise, lending the depth of research and product implementation experience necessary for building a common description framework for the Web. Participants include representatives from Hewlett Packard, Nokia, IBM, AGFA, ILRT Institute for Learning and Research Technology at the University of Bristol, IWA International Webmasters Association and the University of West Florida. The RDF Core Working Group builds on the contributions of many other organization which developed the RDF Model and Syntax (1999 Recommendation) and RDF Schema (1999 Proposed Recommendation).

The W3C Web Ontology Working Group carries a complement of industrial and academic expertise, lending the depth of research and product implementation experience necessary for building a robust ontology language system. Participants include representatives from Agfa-Gevaert N. V; Daimler Chrysler Research and Technology; DARPA; Defense Information Systems Agency (DISA); EDS; Fujitsu; Forschungszentrum Informatik (FZI); Hewlett Packard Company; Ibrow; IBM; INRIA; Ivis Group; Lucent; University of Maryland; Mondeca; Motorola; National Institute of of Standards and Technology (NIST); Network Inference, Nokia; Philips, University of Southampton; Stanford University; Sun Microsystems; Unicorn Solutions along with invited experts from German Research Center for Artificial Intelligence (DFKI) Gmbh; the Interoperability Technology Association for Information Processing, Japan (INTAP); and the University of West Florida.

OWL brings together a number of groups that have been developing Web ontology languages over the past decade. OWL is based the DAML+OIL language, which was developed by an international team funded by the US Defense Advanced Research Projects Agency (DARPA) and the European Commission's Information Science Technologies (IST) program. The documents released today represent the maturation of this work shaped by the members of the the World Wide Web Consortium.

About the World Wide Web Consortium (W3C)

The W3C was created to lead the Web to its full potential by developing common protocols that promote its evolution and ensure its interoperability. It is an international industry consortium jointly run by the MIT Computer Science and Artificial Intelligence Laboratory in the USA, the European Research Consortium for Informatics and Mathematics (ERCIM) headquartered in France, and Keio University in Japan. Services provided by the Consortium include: a repository of information about the World Wide Web for developers and users, and various prototype and sample applications to demonstrate use of new technology. To date, nearly 400 organizations are Members of the Consortium. For more information see http://www.w3.org/.

Testimonials for W3C's Semantic Web Recommendations -- RDF and OWL

The following testimonials are in support of W3C's Semantic Web Recommendations on RDF and OWL. They are provided by:

Adobe Systems, Aduna BV, Agfa-Gevaert N. V., Boeing, Brandsoft, Inc., Institute for Learning and Research Technology, University of Bristol, Creative Commons, DARPA, Fujitsu, HP, IBM, INRIA, Maryland Information and Network Dynamics (MIND) Laboratory, University of Maryland (UMBC), McDonald Bradley, Inc. (MBI), Mondeca, Mozilla Foundation, Network Inference, Ltd., Nokia, Profium, Semaview, Inc., University of Southampton, Sun Microsystems, Inc., and TopQuadrant.

Adobe Systems

As the leading provider of content creation tools to help people communicate better, adding intelligence to media via metadata was integral to our strategy. We developed Adobe XMP (Extensible Metadata Platform) based on RDF, because it provided a flexible and interoperable framework for fostering the capture, preservation, and interchange of metadata across digital media and workflows. The Adobe Creative Suite provides a design platform that enables creative professional to create information rich assets powered by XMP that can be more effectively repurposed and consumed across multiple media and diverse domains.

David Burkett, Director of Product Management, Adobe Systems

Aduna BV

Aduna B.V., located in Amersfoort, The Netherlands, http://aduna.biz/, is very pleased to see both RDF and OWL become W3C recommendations. For a company at the forefront of the developing products based on Semantic Web technology, stable and well-engineered language standards are crucial for our development work, for our products and for our customers. Our current products such as the Sesame platform for storing and querying meta-data heavily exploits the open framework that RDF provides, and we expect to move to the use of OWL in the future. We will continue to support the open standards defined by W3C by our continued development of both commercial and open source software based on these standards.

Martien van Steenbergen, CEO , Aduna BV

Agfa-Gevaert N. V.

The Semantic Web is the representation of data on the World Wide Web. It gives information a well-defined meaning, better enabling computers and people to work in cooperation. Being committed to open standards, AGFA actively participates in the Semantic Web Activity and is very glad to see RDF and OWL as a W3C Recommendation. They are great, for instance, to categorize medical images and their related data.

Jos De Roo, RDFCore and WebOnt WG member, AGFA Gevaert N.V.

Boeing

Boeing is a member of the W3C and is an early adopter of RDF, OWL and related Semantic Web technologies. Boeing has a number of projects exploring semantics-based applications in various areas including information and application integration and interoperability, publish/subscribe, knowledge management and network centric operations. These technologies are expected to have a strong impact on future Boeing programs. Ontologies have become fairly widespread in their use and automated reasoning tools are becoming mature. The time is ripe for standards in this area, and for widespread tool support from vendors.

James L. Phillips, Director, Mathematics and Computing Technology, Boeing Phantom Works

Brandsoft, Inc.

Brandsoft's product offerings are one of the first commercial implementations of Semantic Web components, mainly RDF. Our belief is that enterprises that standardize on a common metadata framework, like RDF, will gain significant value, agility, and substantial cost reduction. They will also benefit from the ability to provide value added services and applications within their extended enterprise community (employees, customers, partners, etc.). As a result of using RDF, Brandsoft has developed a standards based platform with the ability to integrate the various tools needed to: Create, manage and reuse content; Publishing capabilities for differing languages, media, and devices; Establish relationships between people, processes, and systems.

Frank Careccia, Vice President, Engineering and CTO, Brandsoft, Inc.

Institute for Learning and Research Technology, University of Bristol

The University of Bristol is delighted to see the publication of the W3C RDF and OWL Recommendations. The University is a strong supporter of open standards and a long-term participant in the RDF work and considers the Semantic Web as important in developing advanced learning and research technologies for education. Successful RDF-based projects at the University include representing metadata schemas, describing thesauri, events and calendaring, syndicating news, web site annotation and trust and smarter web searching for digital libraries. The University intends to continue developing projects, software and services based on this work.

Alison Allden, Director, Institute for Learning and Research Technology (ILRT), University of Bristol

Creative Commons

The efforts of Creative Commons to encourage permitted sharing and reuse of works are greatly enhanced by the availability and continued development of RDF, which serves as the machine-readable layer for our "some rights reserved" licenses. One year after launch there are over one million Creative Commons-licensed works published on the web, supported by RDF-aware blog, browser, graphics, music, publishing, search and validation applications and services. The upcoming new and revised components of the RDF specification suite will provide a great boost to the understanding and adoption of RDF, and thus our work to cultivate an ecology of Creative Commons-aware software.

Mike Linksvayer, CTO, Creative Commons

DARPA

The DARPA Agent Markup Language (DAML) program is pleased to endorse the OWL Web Ontology Language produced by the W3C Web Ontology Working Group based on the DAML+OIL language developed by the DAML program and its European Union collaborators. We view OWL as a major advancement for the Semantic Web, and have been using it extensively as part of our on-going work to develop Semantic Web tools, rules, and services. We look forward to the wide scale deployment of OWL on the World Wide Web.

Mark Greaves, Program Manager, Defense Advanced Research Projects Agency, U.S. Department of Defense

Fujitsu

Fujitsu Laboratories of America - College Park is currently using OWL as an integral part of our work on "Task Computing." Task Computing is a novel integration of the Semantic Web with Web Services to provide users with easier ways of achieving complicated goals in mobile and/or ubiquitous computing environments. Ontologies defined in OWL give us a powerful mechanism for reasoning about the composition of heterogeneous services and the use of Web Services lets us access real devices and displays. Together they enable new and rich forms of interaction between users and their computing environment. The standardization of OWL and RDF will facilitate the acceptance of innovative software methods such as Task Computing.

Dr. Kazuhiro Matsuo, Senior Vice President and General Manager, Fujitsu Laboratories of America

HP actively supports the development of the Semantic Web and welcomes the new RDF and OWL Recommendations. HP's Semantic Web developers' framework, Jena, (http://jena.sourceforge.net/) is an open-source, freely available, implementation of both Recommendations, with a large and active developer community. We look forward to the Web-scale machine integration of knowledge and information that these new Recommendations support.

Per-Kristian Halvorsen, Vice-President and Center Director, Solutions and Services Research Center, HP Laboratories

IBM

IBM has a history of using progressive research to deliver business value today and in the future. Our research work with the Semantic Web has the potential to open the Internet to even more powerful applications. Within IBM we have many active research projects working with both RDF and OWL. Our first public Semantic Web project, SnoBase, released on AlphaWorks, is a framework for loading ontologies from files and using the Internet for locally creating, modifying, querying, and storing ontologies. It provides a mechanism for querying ontologies and an easy-to-use programming interface for interacting with vocabularies of standard ontology specification languages including RDF, RDF Schema, and OWL. SnoBase can help a broad range of business applications that need knowledge sharing and reuse as well as information search and navigation by using reasoning within a generic management environment.

Alfred Z. Spector, vice president, Services and Software, IBM Research

INRIA

INRIA is pleased to see the publication of OWL and RDF as W3C Recommendations. They will provide standard and stable grounds for our developments on searching Web resources - through the CORESE search engine - and on adapting knowledge sources - through the Transmorpher transformation engine and alignment tools. INRIA already takes advantage of available API for OWL and RDF, and expects these developments to boost the Semantic Web deployment.

Gérard Giraudon, Director for Development and Industrial Relations, INRIA

The Maryland Information and Network Dynamics (MIND) Laboratory at the University of Maryland focuses on helping to speed up the transition of research into practice by partnering with industrial and/or government teams in projects focused on advanced technology deployment. The Semantic Web was identified by our lab as a priority area for this transition, and we are working with a diverse set of partners in bringing this important technology into wider practice. The MIND Laboratory is proud to have co-chaired the Web Ontology Working Group and believes OWL will be an important language in bringing the Semantic Web to its full potential.

Jim Hendler, Director of Semantic Web and Agent Technologies, MIND Laboratory, University of Maryland

Maryland Information and Network Dynamics (MIND) Laboratory

The use of ontologies is a key requirement for realizing the ubiquitous computing vision. Ontologies defined in the Web Ontology Language OWL can help ubiquitous and pervasive computer systems to share information and knowledge, reason about their environment and interoperate. The Semantic Web in UbiComp Special Interest Group is an international group of researchers from academia and industry that is using OWL for pervasive computing applications and defining ontology-driven use cases demonstrating aspects of the ubiquitous computing vision.

Harry Chen, Department of Computer Science & Electrical Engineering, University of Maryland, Baltimore County

McDonald Bradley, Inc.

McDonald Bradley, Inc. (MBI) is leveraging the expressiveness and flexibility of the Resource Description Framework (RDF) today in its support of many Department of Defense and Intelligence Community customers. Specifically, the RDF model was a core design feature of the DOD Discovery Metadata Specification (DDMS) Schema. RDF achieving the status of W3C Recommendation will increase the number of tools while stabilizing their maturity and features. This will enable MBI to better deliver robust Semantic Web applications to its customers as they move towards Net-Centric applications.

Michael C. Daconta, Chief Scientist, Advanced Programs Group, MBI

Mondeca

Mondeca is happy to welcome the advancement of OWL to W3C recommendation. Always eager to make its technology conformant to the widest range of semantic standards, the company has started to use OWL since mid-2003 in customers applications, to describe and set up knowledge models in its ontology-driven knowledge management platform, ITM. ITM ontology layer was beforehand specified using proprietary internal representation. Using OWL provides ITM with new capacity to describe it in a standard and interoperable format, to re-use customer-defined or public domain ontologies, and paves the way to future developments integrating the power of inference tools.

Bernard Vatant, Senior Consultant, Knowledge Engineering, Mondeca

The Mozilla Foundation

RDF gives us a data model for describing information organization structures (metadata) for collections of networked information. Mozilla uses it as a standard way to represent the many different structures we use to organize the various kinds of information we handles --- from bookmarks and email folders to address books and web services. RDF remains important on the browser side not only because of these current uses but also because of developing trends such as web logs and news feeds that are based on RDF. This ability to deal with meta-data independent of the protocols and formats associated with the data is essential in moving the web forward.

Ben Goodger, Lead Engineer, Mozilla Firebird, The Mozilla Foundation

Network Inference, Ltd.

Network Inference congratulates the co-chairs and members of the W3C's Web-Ontology (WebOnt) Working Group for their outstanding work on OWL. OWL is a core component in building the semantic web, and in delivering the means for true machine interoperation. OWL is central to the solutions that Network Inference is fielding with enterprises today. The quality of the Working Group's members, activities and outputs provide OWL with robustness and integrity, and instill the level of confidence in the language which is required for wide adoption. Network Inference is committed to continuing to active contributions to W3C's efforts in this area.

Jack Berkowitz, Vice President, Engineering, Network Inference (Holdings) Ltd

Nokia

Nokia congratulates the W3C on the promotion of the new RDF and OWL specifications to full recommendations, which are expected to provide a solid foundation for the development of the Semantic Web. Having participated actively in both the RDF Core and Web Ontology Working Groups since their inception, Nokia is well aware of the enormous effort that has gone into this work, and applauds the hard-earned success of the Working Group members.

Timo Poikolainen, Vice President of Marketing, Technology Platforms, Nokia

Profium Ltd.

Profium is pleased to see updated RDF specifications reach recommendation status with W3C. Profium has been promoting the use of Semantic Web technologies with its flagship product Semantic Information Router (SIR) since its introduction in April 2001. Profium sees the power of RDF and OWL best unleashed in the context of portal solutions that ask for metadata repositories that can index both content and service descriptions.

Janne Saarela, Managing Director, Profium Ltd.

Semaview, Inc.

Semaview understands the immense value of the emerging Semantic Web and currently provides RDF versions of every calendar published onto the eventSherpa Network. As more semantic islands are created and connected, using RDF and OWL, new and exciting technology services will be created. Semaview believes that innovation will flourish with the birth of this truly intelligent Internet based on the W3C's Semantic Web work.

Paul Cowles, VP, Development and Operations, Semaview, Inc.

University of Southampton

The University of Southampton and the Advanced Knowledge Technologies interdisciplinary research collaboration (AKT IRC) enthusiastically endorse the W3C Resource Description Framework recommendations. The RDF suite of specifications are fundamentally important to the success of the W3C's Semantic Web initiative. RDF provides a common framework for the expression of metadata and metadata schemata. Such metadata support the semantic annotation of Web content and services, which underpin knowledge integration and exchange. A number of leading research projects within the University and AKT IRC are making extensive use of RDF, including our scalable open-source RDF repository software, 3store.

The University of Southampton and the Advanced Knowledge Technologies interdisciplinary research collaboration (AKT IRC) enthusiastically endorse the W3C OWL Web Ontology Language recommendation, a key specification in the W3C's Semantic Web initiative. OWL permits the definition of sophisticated ontologies, a fundamental requirement in the integration of heterogeneous information content. OWL ontologies will also be important for the characterization of interoperable services for knowledge-intensive processing on the Web. Research on next-generation products and services within the University and AKT IRC is incorporating OWL as standard.

Professor Nigel Shadbolt (Director), Professor David De Roure (Head of Grid and Pervasive Computing), and Dr Nicholas Gibbins, AKT IRC, University of Southampton

Sun Microsystems, Inc.

Sun Microsystems, a member of the W3C and the Web Ontology Working Group, wishes to congratulate the co-chairs and members of the W3C working groups on the successful publication of the RDF and OWL recommendations. Sun's own internal enterprise ontology management solution is based on RDF and associated Semantic Web technologies. RDF provides Sun with the foundation for superior knowledge aggregation and application integration.

Lew Tucker, V.P. Internet Services, Sun Microsystems, Inc.

TopQuadrant

TopQuadrant is encouraged by today's announcement and strongly supports W3C's standardization of OWL. Our Government clients understand that the demands of e-Government solutions, such as Federal Enterprise Architecture, digital preservation (NARA) and aerospace programs (NASA) go beyond the current capabilities of XML. They realize that semantic technologies are essential and, in particular, that OWL is critically important for consistent and flexible enterprise data integration. In response to strong interest expressed by our clients, TopQuadrant offers a continuing program of Briefings and Workshops on Semantic Technologies that showcase the use of RDF(S) and OWL.

Robert Coyne, President, TopQuadrant

Contacts

Contact Americas, Australia
Janet Daly
Email: <janet@w3.org>
Tel: +1.617.253.5884 or +1.617.253.2613

Contact Europe
Marie-Claire Forgue
Email: <mcf@w3.org>
Tel: +33.492.38.75.94

Contact Asia
Yasuyuki Hirakawa
Email: <chibao@w3.org>
Tel: +81.466.49.1170

[This announcement is also available in French and Japanese.]

Prepared by Robin Cover for The XML Cover Pages archive. See details in the news story: "W3C Recommendations: Resource Description Framework (RDF) and Web Ontology Language (OWL)."