JavaScript primitive types and corresponding objects

Question

In JavaScript not every data is an object. There exist a few primitive types, like strings, numbers and Boolean which are not objects. For each of these types there exists a

Answer 1

What is the advantage of keeping two separate representations for numbers, strings and Booleans?

Performance

In what context could one need the distinction between primitive types and objects?

Coercion comes to mind. 0 == false while new Number(0) != false

So for instance:

var a = new Boolean(false);
if(a) {
  // This code runs
}

but

var a = false;
if(a) {
  // This code never runs
}

You can read more about coercion here: JavaScript Coercion Demystified