[naasking]

Types and Programming Languages is the go to book, and it's very accessible despite being a textbook:

https://mitpress.mit.edu/books/types-and-programming-languag...

You can find some earlier PDF drafts online if you Google.

[alexashka]

I have the book and I must warn people, it is not THAT accessible - this is not evening reading for an hour, this is work.

[naasking]

You'll have to define accessible then. Learning anything takes work.