Why is typeof null “object”?

Question

I\'m reading \'Professional Javascript for Web Developers\' Chapter 4 and it tells me that the five types of primitives are: undefined, null, boolean, number and string.

Answer 1

If null is a primitive, why does typeof(null) return "object"?

in short: it is bug in ECMAScript, and the type should be null

reference: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/null