title: jQuery "Uncaught TypeError: undefined is not a function" when using fadeIn();
body: <p>I am new to JS and I am writing a basic jQuery-rich webpage with fade-in/fade-out for each page in the same document (using the same div element with separate IDs). Anyway, when I try to fade in the current page, I receive the error "Uncaught TypeError: undefined is not a function", I've had a search around online but couldn't find a solution.</p>
  
  <p>The HTML is loaded before the script and the full jQuery library has been included in the header of the page.</p>
  
  <p>The div element I am targeting has "display: none;" set in my CSS.</p>
  
  <p><strong>HTML</strong></p>
  
  <pre><code>&lt;div class="page_content" id="page_home"&gt;
  Content removed
  &lt;/div&gt;
  </code></pre>
  
  <p><strong>JS:</strong></p>
  
  <pre><code>&lt;script&gt;
  
  var cp = "page_home";
  var tp = document.getElementById(cp);
  tp.fadeIn('slow');
  
  &lt;/script&gt;
  </code></pre>
  
  <p>Anyone experienced anything similar and have a solution? I'm sure it's something simple, since my code is anyway...</p>