Why does this asp.net postback show XmlHttpRequest type
<p>I have a simple aspx page with a button that has an OnClick handler. When the button is pressed, the POST to the server has the http header</p>

<pre><code>X-Requested-With:XMLHttpRequest
</code></pre>

<p>I don't see why this would be the case. Any thoughts?</p>

<p>The control looks like</p>

<pre><code>&lt;asp:LinkButton ID="btnSubmit" Text="Save Changes" runat="server" 
                                OnClick="btnSubmit_Click"&gt;
 &lt;/asp:LinkButton&gt;
</code></pre>
