Accessible name and description: this section needs to better explain the differences between name and description, and it should take Mac into account. I think it's particularly confusing when an element has both a name and description, because screen readers don't all agree on what to do. Here's my simplified explanation for Windows:

Windows:
The name is the primary accessible text, it's what a screen reader uses to announce an object.
The description is extra accessible text, it may not be part of a short announcement.

On Mac, it's totally different:
The title is the visible text of an object, if any.
The description is accessible text; if present, it overrides any visible title and used instead as the accessible text. The description is what's always read, if present - the title, if prseent and distinct from the description, is what's only read optionally.

I probably got both of these descriptions wrong. I'm hoping that by posting a wrong answer I'l inspire people to correct me.