[qcnguy]

Yeah but I think when it was introduced it wasn't a thing you could use separate from the rest of UWP. What changed in Win10 was you could use WinRT APIs from regular Win32 apps too. They started breaking UWP up into independent pieces.

Or not. I haven't thought about this stuff for years. Definitely possible I forgot the ordering of things.

[DiabloD3]

UWP most certainly did not exist when WinRT came into existence. WinRT, itself, is also more or less the third version of this attempt: Managed C++ came first, then C++/CLI, then the WinRT era and C++/CX.

C++/CLI and C++/CX are semi-managed, you only need to use the extensions when interacting with WinRT, although you're free to write your entire app in that dialect.