XML Tree

ML documents form a tree structure that starts at "the root" and branches to "the leaves".

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An Example XML Document

XML documents use a self-describing and simple syntax:

Tove Jani Reminder Don't forget me this weekend!

The first line is the XML declaration. It defines the XML version (1.0) and the encoding used (ISO-8859-1 = Latin-1/West European character set).

The next line describes the root element of the document (like saying: "this document is a note"):

The next 4 lines describe 4 child elements of the root (to, from, heading, and body):

Tove Jani Reminder Don't forget me this weekend!

And finally the last line defines the end of the root element:

You can assume, from this example, that the XML document contains a note to Tove from Jani.

Don't you agree that XML is pretty self-descriptive?

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XML Documents Form a Tree Structure

XML documents must contain a root element. This element is "the parent" of all other elements.

The elements in an XML document form a document tree. The tree starts at the root and branches to the lowest level of the tree.

All elements can have sub elements (child elements):

.....

The terms parent, child, and sibling are used to describe the relationships between elements. Parent elements have children. Children on the same level are called siblings (brothers or sisters).

All elements can have text content and attributes (just like in HTML).

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Example:

The image above represents one book in the XML below:

Giada De Laurentiis 2005 30.00 J K. Rowling 2005 29.99 Erik T. Ray 2003 39.95

The root element in the example is . All elements in the document are contained within .

The element has 4 children: