Update 2004-12-01: "OWL Web Ontology Language for Services (OWL-S) Specification Submitted to W3C." W3C has received a multi-part OWL Web Ontology Language for Services (OWL-S) specification as a Member Submission from participants in the OWL Services Coalition. OWL-S, formerly DAML-S, proposes a framework based on the W3C OWL Web Ontology Language, designed to help users and agents search, discover, invoke, compose and monitor Web services. OWL-S includes eight ontologies written in OWL as an extensible core, explained in two expository documents.

[January 08, 2004] OWL-S Version 1.0 has been released for public review by members of the OWL Services Coalition. OWL-S (formerly DAML-S) is "an OWL Web service ontology which supplies Web service providers with a core set of markup language constructs for describing the properties and capabilities of their Web services in unambiguous, computer-intepretable form." The OWL Web Ontology Language was published by W3C as a Proposed Recommendation on December 15, 2003. OWL is "used to publish and share sets of terms called ontologies, supporting advanced Web search, software agents, and knowledge management. It is designed for use by applications that need to process the content of information instead of just presenting information to humans. OWL facilitates greater machine interpretability of Web content than that supported by XML, RDF, and RDF Schema (RDF-S) by providing additional vocabulary along with a formal semantics. OWL has three increasingly-expressive sublanguages: OWL Lite, OWL DL, and OWL Full." The OWL-based Web Service Ontology (OWL-S) Version 1.0 "features a number of refinements to the Service Profile and Process Model. The Service Profile is used to concisely represent the service in terms of capabilities, provenance, and operational parameters (e.g. cost-of-use, quality-of-service parameters, etc), for constructing both advertisements and requests. Version 1.0 offers clarification and simplification of capability description parameters (i.e., inputs, outputs, preconditions and effects), a tighter integration with the process model, and better organization/modularization of the Profile constructs."

Introduction to OWL-S

"The Semantic Web Services arm of the DAML program is developing an OWL-based Web Service Ontology, OWL-S (formerly DAML-S), as well as supporting tools and agent technology to enable automation of services on the Semantic Web.

OWL-S supplies Web service providers with a core set of markup language constructs for describing the properties and capabilities of their Web services in unambiguous, computer-intepretable form. OWL-S markup of Web services will facilitate the automation of Web service tasks including automated Web service discovery, execution, interoperation, composition and execution monitoring. Following the layered approach to markup language development, the current version of OWL-S builds on top of OWL..."

Note that the focus of the Version 1.0 release is on a language for use in describing Web services. Related matters such as software components, tools, use cases, and architectural considerations are not covered here in detail. However, many requirements in these areas are being considered in developing this language, and as the scope of this working group expands..." [from the OWL-S home page]

OWL Web Ontology Language Proposed Recommendation

On December 15, 2003 W3C announced the advancement of the OWL Web Ontology Language (OWL) to the level of Proposed Recommendation. A W3C Proposed Recommendation is "a mature technical report that, after wide review for technical soundness and implementability, W3C has sent to the W3C Advisory Committee for final endorsement." The working group invited comments on the Proposed Recommendation through 19-January-2004.

"The Semantic Web is a vision for the future of the Web in which information is given explicit meaning, making it easier for machines to automatically process and integrate information available on the Web. The Semantic Web will build on XML's ability to define customized tagging schemes and RDF's flexible approach to representing data. The first level above RDF required for the Semantic Web is an ontology language what can formally describe the meaning of terminology used in Web documents. If machines are expected to perform useful reasoning tasks on these documents, the language must go beyond the basic semantics of RDF Schema..."

The OWL language is presented in six parts:

• OWL Web Ontology Language Overview. A simple introduction.
• OWL Web Ontology Language Guide. Demonstrates OWL through an extended example and provides a glossary.
• OWL Web Ontology Language Reference. A compact, informal description of OWL modelling primitives.
• OWL Web Ontology Language Semantics and Abstract Syntax. Normative definition of the OWL language.
• OWL Web Ontology Language Test Cases. Test cases illustrating correct OWL usage, the formal meaning of constructs, and resolution of issues. Specifies conformance.
• OWL Web Ontology Language Use Cases and Requirements. Usage scenarios, goals and requirements for a Web ontology language