We each create “clouds” of our own tags which evolve into “folksonomies”, or home-made taxonomies of meaning.

Folksonomies and tagging are useful, but we lack the common language needed to make our digital treasures universally useful.

Folksonomies are thus a bottom-up complement to more formalized semantic Web technologies, as they rely on emergent semantics [24, 25] which result from the converging use of the same vocabulary.