THE XML REVOLUTION - TECHNOLOGIES FOR THE FUTURE WEB

A conceptual view of XML

An XML document is an ordered, labeled tree:

character data leaf nodes contain the actual data (text strings)
- usually, character data nodes must be non-empty and non-adjacent to other character data nodes
elements nodes, are each labeled with
- a name (often called the element type), and
- a set of attributes, each consisting of a name and a value,
and these nodes can have child nodes

A tree view of the XML recipe collection:

The tree structure of a document can be examined in the Explorer and Mozilla browsers.

In addition, XML trees may contain other kinds of leaf nodes:

Unfortunately, XML is not as simple as it could be, and there is still no agreement on XML tree terminology :-(