Container vs. Empty Element

Can someone please tell me how to know if a tag should be
a container or an empty element? I have looked at every
DTD that I could find and they don't seem to indicate what
a tag is there. I know that there are things like <em> that
are absolutly containers, and that there are things like
<p> which are becoming containers (chrysilis I guess). But 
what I want to know is how to tell the ones that should
never be a container. Like <hr>. I would think that it should
never be a container.

Secondarily, does anyone have an absolute list of what can
be embeded in what? 

For example, should I use:

<li><h2> Blah </h2> or 
<h2><li> Blah 
<li> Blah </h2>

Does </li> make a difference above? If I want to make a 
head2 list item and have the text after the end of the head2
still indent like a list item, is that allowed? 

I am not looking for answers to specific formatting questions here.
I am trying to give examples of behavior that I have seen, and 
get a general rule of thumb on how it know what it should
do.

Thanks

Mary

Received on Monday, 5 December 1994 15:49:15 UTC