On Savannah: What are "arch" and "bidi" and ....

[Alan Mackenzie]

At the risk of appearing stupid, would somebody please tell me the
purpose of the various named branches in the Emacs CVS repository.  I've
been seeing these names bandied about on the emacs-devel mailing list for
months, and haven't had the courage to ask before now.

I mean, one would have thought that the arch branch was a part of tree,
sweeping elegantly upwards from low down on the trunk, perhaps covering a
neighbouring path with luscious leaves, sheltering from the rain those
standing under it.

And I always thought a bidi was a low sink one sat in to, well, wash
something or other in.

Is "arch" short for "architecture" or "archive" or something else?

"RC" is often used to identify a large and powerful Christian sect.

So, what are the "arch", "bidi", "lexical", "multi-tty", "RC", (Miles's)
"tiling", "Unicode" branches for?  Is there anywhere on savannah I could
have looked to find the answer myself?

Thanks in advance for the answers!

-- 
Alan Mackenzie (Munich, Germany)
Email: aacm@muuc.dee; to decode, wherever there is a repeated letter
(like "aa"), remove half of them (leaving, say, "a").