play the role of an inference engine. The most recent advancement of knowledge-based systems has been to adopt the technologies, especially a kind of logic called description logic, for the development of systems that use the internet. The internet often has to deal with complex, unstructured data that cannot be relied on to fit a specific data model. The technology of knowledge-based systems, and especially the ability to classify objects on demand, is ideal for such systems. The model for these kinds of knowledge-based Internet systems is known as the Semantic Web. See also Knowledge representation and reasoning Knowledge base Knowledge modeling Inference engine Reasoning system Case-based reasoning Expert system Conceptual graph Semantic web Neural networks Rule-based system References Further reading Artificial intelligence