While there are really nice definitions for Hindley-Milner and dependent type, there is nothing about what System F is and how it works. So, it would be nice if System F also gets a blurb in the common terms section.
Thanks for the issue. I've added a short explanations which should give some intuition what System F is and why it is useful, as well as a link to the wikipedia page and references to the undecidability (or not) of type inference. Let me know if I could add anything else!