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» Requirements from Industry
» Vision of the Semantic Web
» Service Oriented Architecture
» Semantic Web Services
» How to enable Semantic Web Services
» Market Expectations - Roadmap
There is an trend towards intra- and inter-organizational networks and emerging move towards structures of open loosely coupled, dynamically bound systems. Technical interoperability (e.g. protocols and interfaces) in this kind of setting is crucial, but it is not always enough to make information systems capable to interoperate seamlessly in a networked world. Semantically interoperability is needed as well in order to enable more sophisticated features to service provisioning and management. If information systems do not “understand” the meaning of the data, large scale integration and higher levels of automation might become inflexible.
Use of Semantic Web technologies is not limited to WWW; they can be applied in other areas as well. Applying Semantic Web technologies has a potential to help in these challenges which are faced by many industries, which include, in addition to what is listed above, e.g. information overload, stovepipe system and poor content aggregation (Slides 3 and 4 in the presentation  Vision of the Semantic Web*).
“Semantic Web is an extension to the current World Wide Web, in which information is given a well-defined meaning, better enabling computers and people to work in cooperation. The Semantic Web will bring structure to the meaningful content of Web pages, creating an environment where software agents can carry out sophisticated tasks for users.” [Berners-Lee, Hendler & Lassila 2001] Shortly, Semantic Web is about making web understandable by machines. (Slide 5 in the presentation Vision of the Semantic Web*)
The Semantic Web principles are implemented in the layers of Web technologies and standards. Figure illustrates the architecture of the Semantic Web as it is envisioned by Berners-Lee [2001]. (Slide 6 in the presentation Vision of the Semantic Web*)
To philosophers, term ontology refers to an esoteric field in philosophy that studies being, order and structure of reality – what there is in the world. However, the same term is also adopted as a critical part of the concept of Semantic Web.
Ontologies try to capture the meaning (semantics) of a particular subject area of a knowledge (domain) that corresponds to what a human beings know about that domain. An ontology also characterizes that meaning in terms of concepts and their relationships. Ontologies enable sharing semantics of your data across distributed applications. An Ontology can be seen as an agreement between partners, in which they agree about the relationships and concepts previously discussed, providing this way, a communication mechanism inside a specific domain of interest. (Slides 7 and 8 in the presentation Vision of the Semantic Web*)
A description of an Ontology usually consists of the classes (general things) in the domains of interest and instances (particular things) of the classes. Sometimes classes are called concepts, relationships among these things, properties (and property values) of these things, functions of and processes involving these things and constraints on and rules involving classes and relationships. (Slide 10 in the presentation Vision of the Semantic Web*)
Ontologies can be presented in graphical and also in textual format with knowledge representation language. (E.g. OWL) These languages are typically based on some logic, the logic itself being a formal language with a syntax and semantics. A consequence of this is that high-end ontology languages are backed by a precise formal logic, which thereby makes the ontology machine interpretable. (Slide 11 in the presentation Vision of the Semantic Web*)
Semantic Web and Web services go hand in hand. Semantic Web is not just for the World Wide Web. It represents a set of technologies that will work equally e.g. in Web service world, too. Current Web services technology is basically a syntactical solution and the semantical part is missing. Web services combined with Semantic Web technologies enable Semantic Web services. Just like semantically annotated web pages, they are machine interpretable.
See Vision of the Semantic Web*
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