The Ontology of Tags

Social bookmarking sites such as Flickr, del.icio.us, and CiteULike have adopted folksonomic systems where users tag entities with keywords. These tagging systems replace traditional taxonomic systems that employ hierarchical categorization schemes. While there are some differences in how these tagging systems are constructed, e.g., as broad or narrow folksonomies, there has been confusion as to whether tagging constitutes a collaborative activity or a collective one. The distinction between collaborative and collective influences the theoretical assumptions upon which research is conducted. Researchers have adopted a semiotic theoretical perspective as an avenue for discerning emergent semantics of folksonomies. If tagging systems are to be useful to social media or semantic technologies, if we are to indeed discern the semantics emergent from folksonomies, then we need to understand the ontology of tags. This paper examines some of the fundamental ontological assumptions regarding tagging and folksonomies