It works well even if I delete JavaScript:void(0), why?
<p>The following code is from 'JavaScript by Example Second Edition',the window will be colsed when I click "Click here to close little window".</p>

<p>I find it works well too even if I replace href="JavaScript:void(0)" with href="", why ? </p>

<p>Thanks!</p>

<pre><code>&lt;html&gt;
&lt;head&gt;&lt;title&gt;Display Form Input&lt;/title&gt;
&lt;script type="text/javascript"&gt;
  function showForm(myform) {
 NewWin=window.open('','','width=300,height=200');
  name_input="&lt;b&gt;Your name: " + myform.user_name.value
+ "&lt;/b&gt;&lt;br /&gt;";
  NewWin.document.write(name_input);
phone_input="&lt;b&gt;Your phone: " + myform.user_phone.value
+ "&lt;/b&gt;&lt;br /&gt;";
  NewWin.document.write(phone_input);
}
  function close_window(){
NewWin.window.close();
}
&lt;/script&gt;
&lt;/head&gt;
&lt;body&gt;&lt;hr&gt;&lt;h3&gt; Display form data in a little window&lt;/h2&gt;&lt;p&gt;
  &lt;form name="formtest"&gt;
  Please enter your name: &lt;br /&gt;
&lt;input type="text" size="50" name="user_name" /&gt;
&lt;p&gt;
Please enter your phone: &lt;br /&gt;
&lt;input type="text" size="30" name="user_phone" /&gt;
&lt;/p&gt;&lt;p&gt;
  &lt;input type="button"
value="show form data"
onClick="showForm(this.form)"; /&gt;
&lt;/form&gt;
&lt;/p&gt;
&lt;big&gt;
  &lt;a href="JavaScript:void(0)" onClick="close_window()"&gt;
Click here to close little window&lt;/a&gt;
&lt;/big&gt;
&lt;/body&gt;
&lt;/html&gt;
</code></pre>
