This is possibly a pointless question, but i don't find the only answer i can come up with on my own to be at all satisfactory.
When introducing a character with a profession that i find horribly interesting which people may or may not have heard of (in this case, a Doula,) do you find that it's best to set the story aside for a few moments and take the time to explain it, create a conversation or situation within the story in which the character explains his/her profession, or to leave it alone and let the reader research it themselves if they're really all that curious.
Anyway, i get the feeling that it's probably best for a writer to do whatever it is they think feels the best. But, on the off chance that any of these options just don't work out well i decided to ask.
Well, you're writing to communicate. Unless part of what's important about the story is that the reader not understand something, if you're using a word or term that you know most people reading won't understand, then explaining it somewhere, somehow, not necessarily the first time you use it, is a wise idea.
As for how you do it, that's your call. If you do it with enough assurance, you can simply tell people things. Or you can have your characters tell people things. Or you can footnote. Or have a dancing paperclip leap in and explain, then fly out of the story never again to be seen. As you say, do what you think best: that's the joy of being a writer. You get to make your own rules and build your own worlds, and things happen the way you want, because you say so.
There are gorgeous Escher snakes in motion at
http://www.etereaestudios.com/docs_html/snakes_htm/snakes_movie_index.htm (via the ever-impressive Shanmonster).
I heard from Jim Frenkel, packager of YEAR'S BEST FANTASY AND HORROR (formerly the Datlow/Windling one, now the Datlow/Link-Grant book) that they're taking my story from SHADOWS OVER BAKER STREET, "A Study in Emerald", which made me very happy. That story's also been taken for the new Strahan & Haber-edited SCIENCE FICTION: THE BEST OF 2003; and "Closing Time" (From Michael Chabon's McSWEENEY'S MAMMOTH BOOK OF THRILLING TALES) has been taken for the Steve Jones MAMMOTH BOOK OF BEST NEW HORROR anthology. Leading the casual reader to assume that there are an awful lot of stories about mammoths being written these days. All of these things make me very happy.
And demonstrating that this blog has a strange and far-reaching power, beyond what you or I would ever have dreamed, if you go to http://nielsenhayden.com/makinglight/archives/004636.html#004636 you will read about the intersection of Wodehouse, London, and A Certain Argentinean Author, by John M. Ford, inspired by something someone said here last week.
I tried to post this and discovered that the neilgaiman.com server is down. It's a weekend thing, I suppose. Still, it also allows me to throw in a little ray of happiness and sunshine, via Scott McCloud. -- who is now selling, amongst other things, Bucket Full O' Kittens desktop patterns through Bitpass. (You can read the story of the Bucket Full O' Kittens at http://www.scottmccloud.com/comics/mi/mi-24/mi-24.html)