Master the JavaScript Interview: What is a Closure?
Eric Elliott

If you can’t answer this question, you’re a junior developer. I don’t care how long you’ve been coding.

And I would say, I don’t care how long you’ve been interviewing but you’re not good for hiring devs. :P

I really do not agree with this statement. I came across closures 7 years ago, used to solve a problem, I get to use them in the past very often even I did not known the what they were. From my point of view a Closure are nothing concrete but just a trick in Js to protect scope or create private variables or whatever to full fill Javascript missing part to a real coding language.

Not knowing them does not make someone a junior developer, you cannot say that especially when you’re dealing with the worst coding language that became so popular (by the way I love Javascript don’t get me wrong).

Rather I would say someone it’s a javascript junior developer if I show him a closure and he does not understand it, or why it is that way (because probably he does not know very well js)