Computerized information handling has changed its focus from centralized data
management systems to decentralized data exchange facilities. Modern distribution
channels, such as high-speed Internet networks and wireless communication
infrastructures, provide reliable technical support for data distribution and data access,
materializing the new popular idea that data may be available to anybody, anywhere,
anytime. However, providing huge amounts of data on request often turns into a
counterproductive service, making the data useless because of poor relevance or
inappropriate levels of detail. Semantic knowledge is the essential missing piece that
allows the delivery of information that matches user requirements. Semantic
agreement, in particular, is essential to meaningful data exchange.
Semantic issues have long been open issues in data and knowledge management.
However, the boom in semantically poor technologies, such as the Web and XML,
has prompted a renewed interest in semantics. Conferences on the Semantic Web, for
instance, attract crowds of participants, while ontologies on its own has become a hot
and popular topic in the database and artificial intelligence communities.