I believe that .NET Core is not a subset of the .NET Framework; e.g. .NET Core might have things that are not yet in .NET framework. I believe that the things

I believe that .NET Core is not a subset of the .NET Framework; e.g. .NET Core might have things that are not yet in .NET framework. I believe that the things that go into .NET core eventually go into .NET Standard (and thus the framework), but at a slower pace. Thus it would be: .NET ECMA Spec ⊆ .NET Standard ⊆ (.NET Core ∩ Mono ∩ Xamarin ∩ Unity ∩ .NET Framework)