It appears the the Ask Different FAQ is gone, redirecting to a generic help page. I now see that there is a page about what is on-topic for the site, but that page is far less prominent than the old FAQ was.
There's some great explanations of how Stack Exchange works, but it's too hard to find what's specifically appropriate for Ask Different.
The help page is a great resource, but it doesn't mark well enough the function of the first section of the FAQ about what is on-topic here.