title: Fatal error: Call to a member function library() on a non-object
body: <p>I'm using <code>CodeIgniter</code> and when my code try to load</p>
  <pre><code>$this-&gt;load-&gt;library('session');
  </code></pre>
  <p>I get this error:</p>
  <blockquote>
  <p>A PHP Error was encountered</p>
  <p>Severity: Notice</p>
  <p>Message: Undefined property: Appointments::$load</p>
  <p>Filename: controllers/appointments.php</p>
  <p>Line Number: 7</p>
  </blockquote>
  <p>I don't know how to fix this? What's the cause? I should provide something else?</p>