Those are not exclusive to Haskell.

Personally, just from reading the title, I was hoping for an article about the design of type systems in programming languages in general.

... which won't mean much to someone who doesn't know Haskell. The kind of person who might click on this link thinking "types and classes are the same thing, what does he mean 'type class'".

(don't @ me with your pedantic bullshit about how types and classes are different, I don't care).