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HTML DOM Nodes

In the DOM, everything in an HTML document is a node.

Nodes

According to the DOM, everything in an HTML document is a node.

The DOM says:

Look at the following HTML document:

<html>
  <head>
    <title>DOM Tutorial</title> 
  </head> 
  <body> 
    <h1>DOM Lesson one</h1> 
    <p>Hello world!</p> 
  </body> 
</html>

The root node in the HTML above is <html>. All other nodes in the document are contained within <html>.

The <html> node has two child nodes; <head> and <body>.

The <head> node holds a <title> node. The <body> node holds a <h1> and <p> node.

A common error in DOM processing is to expect an element node to contain text.

However, the text of an element node is stored in a text node.

In this example: <title>DOM Tutorial</title>, the element node <title>, holds a text node with the value "DOM Tutorial".

"DOM Tutorial" is not the value of the <title> element!

However, in the HTML DOM the value of the text node can be accessed by the innerHTML property.

You can read more about the innerHTML property in a later chapter.