The <map>'s parent is a <body> tag that's implicitly added during parsing to "fix" the DOM tree.  See Ian Hixie's live DOM viewer for a visual representation of this (paste your HTML into the top textarea):

http://software.hixie.ch/utilities/js/live-dom-viewer/

Dave


From: zhenghe zhang <zhenghe.zhang@gmail.com>
To: webkit-dev@lists.webkit.org
Sent: Wednesday, December 31, 2008 2:12:18 AM
Subject: [webkit-dev] About Dom tree

Hi
    I am studying the "webkit", and now I have a question , I hope you
tell me , thank you!

As follows:

<table width="640" height="530" border="0" cellpadding="0" cellspacing="0">
  <tr>
    <td><img src="images/index.jpg" usemap="#Map" border="0"></td>
  </tr>
</table>
<map name="Map">
  <area shape="rect" coords="110,108,294,148"
href="column.jsp?columnid=JINGCAIDAODU">
</map>

I think the map's parent is the "img", but others don't agree with me.
Please tell me the detail on the basic of DOM tree.

Thanks
zh