Fun Friday Challenge: Why do these two code examples work differently?

example1.js

/* This example results in
 * undefined is not a function
 */
doLog();

var doLog = function() {
  console.log('Log!');
}

example2.js

/* This example results in
 * Log!
 */
doLog();

function doLog() {
  console.log('Log!');
}

Just read an article on JavaScript Scoping and Hoisting. Peterchon is right:
In the first example only declaration of doLog variable will be hoisted and it will receive it's value only at execution time. That is why it's value is undefined as it didn't receive it's value when it is referred to. In the second example doLog function declaration and it's body will be hoisted and so executed in the appropriate order.