New wiki page: 'Explanations'

[denise]

I created the Explanations wiki page after seeing mark waving the code machete tonight: he took out a lot of old and unused stuff, which is great, but a few (very out of date) old server-admin documentation files that were casualties had some explanations of things that I don't think are documented anywhere else.

That does not mean the entire server-admin documentation should survive -- out of date documentation is often worse than no documentation! -- but between that and the talk I gave at LCA, "When Your Codebase Is Nearly Old Enough To Vote", it occurred to me that we should probably document a few of those things that live in our heads that we find ourselves explaining to new contributors -- things like why an entry URL uses the anum and not the jitemid, why you can't just change a text string in a patch and have it update the text on the live site, why you occasionally hear oldtimers calling the Recent Entries page 'lastn', stuff like that.

So, if you've been around for a while and can think of a few things that wouldn't necessarily make sense right off the top of your head -- or if you're new and ran into one or more of those things at some point and had to have someone explain them to you -- please add them to that page! As I said in my talk: institutional memory is a great thing to have, but a lousy thing to have to rely on.