Faceting is tagging, but the tags used are not English words. Facets are abbreviated concepts, with numbers for disambiguation. Combine facets to form tags, with more meaning, but less readability, than English words.
A faceter is an authority with a list of facets. Since anyone can make a list of facets, everyone is an authority. Each facet list from an authority is given a sequential number when first published, so faceters can publish smaller, more focussed lists. Note these with a number after the faceter's initials. For example, CJD1 means facet list "Jason David Catena 1".
Since facets can easily recur, prefix every facet with its faceter, and facet list number, so we know which facet we're talking about. (This constructs a namespace to avoid facet collisions). For example, the tag "CJD1WP1" means "WordPress (Jason David Catena 1)". If this faceter had a facet list for encyclopedic internet sites, "CJD2WP1" could mean "Wikipedia (Jason David Catena 2)".
Append additional facets from the same faceter. Combine facets from different faceters with a space or underscore. For example: the tag CJD1t1t2_diu1tool means "tool trap (Jason David Catena 1), tool (del.icio.us 1)".