Semantic Web gets into collaborative tagging

Collaborative tagging is a new content sharing and organization trend, mainly diffused over the Web, which has attracted growing attention during the last years. It refers to the process by which many users add metadata in the form of keywords to shared content. Today many different collaborative tagging systems are available on the Web, enabling users to add descriptive keywords to different types of Internet resources (web pages, photos, videos, etc.). The great number of advantages offered by the availability of collaboratively tagged resources in terms of their organization and shared information is also underlined by their growing adoption, also in non-technical communities of users. In spite of this, analyzing the actual structure and usage patterns of collaborative tagging systems, we can discover many important aspects which still need to be improved so as to bring tagging systems to their full potential. In particular, problems related to synonymy, polysemy and plural words represent a great limit, causing inconsistencies among the terms used in the tagging process and thus reducing the efficiency of content search and the effectiveness of the tag space structuring and organization. This kind of problems is mainly caused by the lack of semantic information inclusion in the tagging process. Considering the increasing attention focused on the Semantic Web, we propose a new model of tagging system, based on semantic keywords. We let the users easily define the meaning of their tags, referencing some sort of social ontology. As social ontology we explore the adequacy of the support offered by the entries of Wikipedia and WordNet. Finally we present a tool that allows users to tag in a semantic context, providing an evaluation of the system proposed in comparison with classical tagging tools.