Joe, What Andy has done is to use the definition list tags for a purpose other than intended. The DT tage is for Definition Term and DD is Definition Data. Think of it as a dictionary usage. By not supplying data to the DT tag you seem to get an indent. Below is an example with data provided for these two tags and (hopefully) readable tags used to produce it.

Term 1

The definition 1

Term 2

The definition 2

<dl>
<dt>Term 1
<dd>The definition 1
</dt>
<dt>Term 2
<dd>The definition 2
</dt>
</dl>

btw - If you don't need nested indents you can use the <blockquote> </blockquote> pair of tags.