Its hard to explain unless you know html.
In general:
Code:
<div id="parent">
<div id="child1">This is child one because it is contained WITHIN parent</div>
</div><!-- This is end of parent element -->
In this case it looks like:
Code:
<div class="forumrow table">
<div class="foruminfo td"> .... </div>
</div>
so, div.forumrow is the parent of div.foruminfo
I hope that helps.
(firebug also makes this very easy to find without looking at the raw html)