DocBook contains a large number of XML elements from which we only use a subset. Our subset, however, uses other elements than the subset used by Simplified DocBook; that is why we are not using Simplified DocBook (which would otherwise be a nice idea, because many editors support Simplified DocBook only).

Be aware that XML has two special characters that cannot be used literally in text: < (the opening angle bracket) and & (the ampersand sign). Whenever you need to use those two characters literally, you have to use entities, like in this example: <literal> & <programlisting>

We structure our documentation using nested section elements. A book as DocBook defines it would look like this:

<book>
 <chapter>
  <section>
   <section>
    ...
   </section>
  </section>
 </chapter>
 <appendix>
  <section>
   ...
  </section>
 </appendix>
</book>