XML
Markup for arbitrary structured data.
XML is taught here in 3 lessons, running from XML syntax and well-formedness through to Validation with DTD and XSD. Each lesson takes one topic, shows the working code, and links onward to the next, so the course can be read straight through in order.
| Track | XML & Web Services |
| Lessons | 3 |
| Level | Beginner |
| Reading time | about 39 minutes |
| Prerequisites | None beyond being able to open a text editor |
Lessons
- XML syntax and well-formednessElements, attributes, entities and CDATA, plus the exact rules a document must satisfy to be well-formed.
- NamespacesHow URIs disambiguate element names, how default and prefixed namespaces differ, and the attribute trap that breaks XPath queries.
- Validation with DTD and XSDWhat DTDs and XSDs can express, how to write a usable schema, and when XML is still the right choice today.
More in XML & Web Services
XPath XSLT SOAP RESTful APIs RSS & Atom
FAQ
How long does the XML course take?
It has 3 lessons, about 39 minutes of reading. Expect roughly twice that if you type out and run every example.
Do I need prior experience for XML?
No. This is the first course in XML & Web Services, so it starts from the beginning and assumes no background.
What should I read after XML?
Continue with XPath (3 lessons), the next course in XML & Web Services.
Last refreshed 2026-09-18.