ions.html#mom">Mom&#8217;s Document Processing Terms</a>,
are those parts of a document that contain information about the document
itself which appear in the margins either above or below
<a href="definitions.html#running">running text</a>.
They are, in all respects but two, identical.  The differences are:
</p>
<ol style="margin-top: -.5em; margin-bottom: -.5em;">
  <li>headers appear in the margin <i>above</i> running text while
      footers appear in the margin <i>beneath</i> running text;
  </li>
  <l