javascript closure advantages?

Question

Whats the main purpose of Closures in JS. Is it just used for public and private variables? or is there something else that I missed. I am trying to unders

Answer 1

I think the best phrase to sum up the purpose of closures would be:

Data Encapsulation

With a function closure you can store data in a separate scope, and share it only where necessary.

If you wanted to emulate private static variables, you could define a class inside a function, and define the private static vars within the closure:

(function () {
    var foo;
    foo = 0;
    function MyClass() {
        foo += 1;
    }
    MyClass.prototype = {
        howMany: function () {
            return foo;
        }
    };
    window.MyClass = MyClass;
}());