title: Why does `isFinite(null) === true`?
body: <p>The following are examples that make sense to me.</p>
  
  <pre><code>isFinite(5) // true - makes sense to me, it is a number and it is finite
    typeof 5 // "number"
  isFinite(Infinity) // false - makes sense for logical reasons
    typeof Infinity // "number"
  isFinite(document) // false - makes sense as well, it's not even a number
    typeof document // "object"
  </code></pre>
  
  <p>The following is where I get confused.</p>
  
  <pre><code>isFinite(null) // true - Wait what? Other non-number objects returned false. I see no reason?
    typeof null // "object"
  </code></pre>
  
  <p>I just don't see the reasoning behind this. 
  What I'd like is the most low-level answer possible. 
  I think <code>null</code> is being converted to 0, why? What other impacts does this have?</p>