[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