Model structured documents with elements, attributes, namespaces, schemas, parsing, and transformations.
Lessons
Document XML with comments the parser ignores.
XML Comments is easiest to learn by reading the example, changing it, and observing the result.
<?xml version="1.0" encoding="UTF-8"?>
<config>
<!-- Database connection settings -->
<host>localhost</host>
<port>5432</port>
<!-- TODO: move the password to an environment variable -->
</config>Practice the XML Comments example in a small scratch file, then explain what changed and why.