When OS X started, the numbering system began with 10.0, then 10.1, 10.2, etc. Updates were numbered 10.0.1, 10.1.1, 10.2.1, etc. Big Sur started at macOS 11.0 and is now at 11.1 with no number after the final 1. Will the next OS be macOS 12? Something else?

And further to that, why do I sometimes see 10.16?

I'm thinking OS 12.x. Big Sur can run through 11.0 through11.99, and even breaking it down further, can run through 11.1.0 through 11.1.99, 11.2.0 through 11.2.99, etc. Howver, V11.2 is alreday in beta testing, and that will be the next release.

If Apple follows the pattern established in all of their other products there will be a series of upDATEs this year; macOS 11.1, 11.2, up to 11.6 or 11.7. Then next September there will be an upGRADE release, macOS 13. I would not be surprised if sometime in the not too distant future iOS, iPadOS, macOS, WatchOS, TvOS, (& AutoOS?) will have the same version number. They are, after all, based on the same code kernel and the upgrade releases are closely synchronized.

Don't you mean macOS 12? I understand superstitions about the number 13 but I have never heard of dodecaphobia!

macOS version numbering isn’t so simple 'splains it.

The app that generated the drop-down in my image, QuickBoot, dates back to 2011 at the latest.

Okay so I skipped from 2020 directly to 2022. The way this one is starting out, I may want to forget it.