overflowingbra.com story codes

hey

i just joined the forum and i was hoping someone could help me out. when i browse the library at overflowingbra.com, each story has a little series of codes or abbreviations underneath. what do they mean? here's an example:

bg ag chem fa fast ft huge nc offstage tg wow

um? anyway, if anyone could tell me what those codes (and the countless other ones) mean, i'd be very grateful!