As you may have seen, I have started writing a new description of Flat Black for the use of players.
As is my habit, I have been calling this document a “brief”, because I think of it as being like the brief that a solicitor assembles for a barrister to prepare him or her to try a case in court, or that an attorney presents to a judge as a written statement of his or her case. i.e. it contains the necessary information; it is succinct but complete. I am used to supplying players with “briefs” a couple of dozen pages long that will be the only document that they have to read to play a character in the setting described (though they may consult a separate gazetteer of encyclopaedia for details).
This is evidently a confusing usage, not widely understood outside the profession of law. I ought to abandon it. @RogerBW and @DrBob expect a document described as a “brief” to be an epitome or abridgement that is read as preliminary exercise to studying the actual contents.
So. The project in hand is to write a players’ document for Flat Black. I have in mind that it might be 36 to 48 pages long (21,000 to 28,000 words) and require an abstract. It may eventually be supplemented by reference documents, but basically it ought to be the “core book” for players: the text that they own or borrow, skim, refer to, perhaps study, and maybe (if they become fans¹) master.
“Brief” is the wrong word for this work. What should I call it? “Players’ Handbook”? “Players’ Manual”? “Players’ Guide”? “Setting Reference Document”?
I’ve been thinking of the first (small) document as a Players’ Introduction. This might be more of a Players’ Reference.
If I were doing it - and I realise that I’m not, this is your project - I might start each section with something like “History. For more detail, see the Big Book of History. But in brief…”