Why the output is null and not the length(here's the code:)

```
<i>
 <input type="text" name="webAdress" />
<input type="button" value="CheckLegnth" onclick="myFunction()" />
     <script type="text/javascript">
            function myFunction() {
                var webAdress = document.getElementById('webAdress');
                alert(webAdress);
            }

  </script>  
</i>

```