(BOF) (From the saying "Birds of a feather flock together") An informal discussion group, scheduled on a conference program or formed ad hoc, to consider a specific issue or subject. It is not clear where or when this term originated, but it is now associated with the USENIX conferences for Unix techies and was already established there by 1984. It was used earlier than that at DECUS conferences and is reported to have been common at SHARE meetings as far back as the early 1960s.