Other items you may find in XML documents:
Empty elements
- all 3 of these are the same:
- <mac_user></mac_user>
- <mac_user />
- <mac_user/>
Processing instructions
Tag attributes
<person>
<mac_user/>
<personal_name><?php print $name; ?></personal_name>
<phone_number type="ext">51052</phone_number>
</person>