What I meant by basic was the description of types provided by a language - usually in an introductory text you might read when learning a new language. I probably didn't articulate that correctly.

But I guess what I was referring to as a "middle ground"qa any resources for learning about types systems written in a similar approachable tone like this article.

This was another article I read recently that I thought was similarly accessible on the subject of types systems:

https://medium.com/@thejameskyle/type-systems-structural-vs-...

So I guess I'm wondering if there exists such a book or series that might allow one to further their knowledge of type systems without requiring university study.