XSLT and XPATH: A Guide to XML Transformations

1.5. Terminology for XSLT

Now that we have seen some very simple XSLT stylesheets, it is important to understand the way in which both XSLT and XPath refer to their parts. For instance, while you may be familiar with “root elements,” the distinction between them and the “root” or "document root” might not be clear. Similarly, the idea of nodes and document order may be generally clear, but their precise applications deserve attention.

1.5.1. The Root of the Matter

The definition of root, shown below, supplies key concepts for working with XSLT stylesheets and other XML document instances.

root: A unique node or vertex of a graph from which every other node can be reached.

[first computer usage] Formally, a tree is a set of nodes connected by ...