Javascript - difference between namespace vs. closure?

Question

In Javascript, what\'s the difference between a namespace and a closure? They seem very similar to me.

EDIT

Specifically, this article discusses namesp

Answer 1

A namespace is essentially an Object with no interesting properties that you shove stuff into so you don't have a bunch of variables with similar and/or conflicting names running around your scope. So, for example, something like

MyNS = {}
MyNS.x = 2
MyNS.func = function() { return 7; }

A closure is when a function 'retains' the values of variables that are not defined in it, even though those variables have gone out of scope. Take the following:

function makeCounter() { 
   var x = 0;
   return function() { return x++; }
}

If I let c = makeCounter() and then repeatedly call c(), I'll get 0, 1, 2, 3, .... This is because the scope of the inner anonymous function that makeCounter defines 'closes' over x, so it has a reference to it even though x is out of scope.

Notably, if I then do d = makeCounter(), d() will start counting from 0. This is because c and d get different instances of x.