Nimforum 2.1.0 is here

[cblake]

Wikipedia calls it "Categories" at the bottom of their English pages. I agree 
"tags" or "labels" is more common in usage by "computer programmers", but they 
are all overlapping/the same idea. It seems the original feature request also 
maybe conflated "tags" with "user definability" a la Twitter hashtags. 
Multiplicity is more important to ease of use than who defines tags, imo 
(though I have nothing against empowering end users).