Adding is_ajax_request() method to CI_Input
diff --git a/user_guide/libraries/input.html b/user_guide/libraries/input.html
index 7044213..d838cf0 100644
--- a/user_guide/libraries/input.html
+++ b/user_guide/libraries/input.html
@@ -239,10 +239,17 @@
 <code>$headers = $this->input->request_headers();</code>
 
 <h2>$this->input->get_request_header();</h2>
-<p>Returns a single 
+<p>Returns a single member of the request headers array.</p>
 
 <code>$this->input->get_request_header('some-header', TRUE);</code>
 
+
+<h2>$this->input->is_ajax_request()</h2>
+<p>Checks to see if the <var>HTTP_X_REQUESTED_WITH</var> server header has been set, and returns a boolean response.</p>
+
+<code>$this->input->is_ajax_request()</code>
+
+
 </div>
 <!-- END CONTENT -->