Folksonomies and ontologies: two new players in indexing and knowledge representation

The current trends of the semantic web and web 2.0 have led to a growing interest in knowledge representation methods. On the one hand ontologies are being designed by knowledge engineers to perform advanced information integration, on the other hand users apply content-descriptive tags to large-scale document collections. These two new systems broaden the spectrum of knowledge representation methods in different directions. Both approaches will be introduced and discussed regarding their novelty, singular characteristics, advantages and shortcomings. The possibilities of combining social tagging with other techniques will also be sketched and proposed for discussion.