Rename "OS X" to "macOS" by gohai · Pull Request #516 · processing/processing-docs

Yeah, starting with Sierra (10.2), it's called macOS. I think we can change it in the docs, but at the moment, we're a little broken on Sierra anyway. And technically, 10.11 and earlier are still Mac OS X. (And System 8.x and earlier is MacOS! I could go on for days…)

I've been just updating it as I go, in particular, when I see a reference that's referring to the whole platform, rather than a specific OS version.

Bottom line, I don't think it's a high priority. It's just Apple marketing crap.