Actually, I think knowing the history and theory behind a language (as appropriate) is very helpful. Particularly, if you're using a language like Haskell or O

Actually, I think knowing the history and theory behind a language (as appropriate) is very helpful. Particularly, if you're using a language like Haskell or Ocaml, it helps to have at least a vague idea of what a functor actually is and where the idea comes from. (I actually only realized that functors were actually similar ideas in both languages a couple days back.) On the other hand, if you're using a language like JavaScript, understanding the history (especially the languages that influenced it) makes understanding some of the "quirks" much simpler. When you see the influence of Scheme, the scoping suddenly makes much more sense, for example. So, over all, I think understanding the background of a language really helps for complete mastery.