title: Why can I not define functions in jQuery's document.ready()?
body: <p>Functions come up as undefined if I place them in the document.ready() function:</p>
  
  <pre><code>$(document).ready(function(){
    function foo()
    {
      alert('Bar');
    }
  });
  
  foo(); // Undefined
  </code></pre>
  
  <p>Why does this happen? I'm sure I'm just in need of some simple understanding :)</p>