title: Why is typeof null "object"?
body: <p>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.</p>
  
  <p>If <code>null</code> is a primitive, why does <code>typeof(null)</code> return <code>"object"</code>?</p>
  
  <p>Wouldn't that mean that <code>null</code> is passed by reference (I'm assuming here all objects are passed by reference), hence making it NOT a primitive?</p>