XML

As long as only well-formedness is required, XML is a generic framework for storing any amount of text or any data whose structure can be represented as a tree. The only indispensable syntactical requirement is that the document has exactly one root element (alternatively called the document element). This means that the text must be enclosed between a root start-tag and a corresponding end-tag.

The diference between XML and HTML is that XML was designed to transport and store data, while HTML was designed to display data.

XPath

XPath may be used to compute values (strings, numbers, or boolean values) from the content of an XML document.

• XPath tutorials
• XPath tools