I know … the request to know what the categories actual mean/are intended to mean has aged gracefully like a good cheese … but it is time for Logos quit stalling. If you don't know what their definitions are you should not be expanding their use; if you know what they are, tell us. We need to know where to look for books especially in the area of guides and bible study - church documents and liturgy are other areas of confusion. The new Book section may be well designed (except for one's own library not being the default and showing first), but it is ruined "guess 'em" data.