ReasoningWeb.org

The Semantic Web

With the abundance of information available on the web it is increasingly becoming necessary to enrich data with semantics, which can, to some extent, be understood and processed by machines. The Semantic Web is a collaborative effort led by the W3C aiming at this goal.

Much of the semantic web effort is currently focused on data modelling aspects, i.e., how to represent the semantic information on the web. Complementary to that there is the reasoning aspect, i.e., how to process the semantic information associated with the data. Reasoning capabilities are sometimes referred to as logic, deductive, or rule-based capabilities.

Almost any specification of reasoning aspects requires some kind of reasoning language. The study of reasoning languages and their processing is therefore the major focus of activities relating to "Reasoning on the Semantic Web".

Reasoning languages can be regarded from different perspectives:

• Application centered.
  This perspective concentrates on how useful a given reasoning language is for the implementation of a given application. Typical applications are web service retrieval and web service composition.

• Functionality centered.
  This perspective concentrates on whether a given reasoning language supports given functionalities. Typical functionalities are ontology reasoning and access validation.

• Reasoning technique centered.
  This perspective concentrates on which reasoning techniques come with a given reasoning language. Typical reasoning techniques are forward and backward chaining, semantic tableaux, constraint reasoning.

The Semantic Web activity has so far resulted in a number of Semantic Web languages and/or reasoning systems, such as DAML+OIL and OWL, BPEL4WS, BPML, DAML-S, ConsVISor, JTP, and Triple. They were developed primarily from the application centered perspective and the functionality centered perspective.

Reasoning techniques have been developed and successfully applied in fields such as computational logic, expert systems, and logic programming.

The development of reasoning languages from the reasoning technique centered perspective, which takes results from those fields into account, is currently still in its infancy. It may, however, become a significant guideline for activities related to "Reasoning on the Semantic Web" in the next future.