In the HTML DOM, everything is a node. DOM is HTML viewed as a tree of nodes.

HTML DOM node syntax

According to W3C's HTML DOM standard, all content in an HTML document is a node:

The entire document is a document node

Each HTML element is an element node

The text within the HTML element is a text node

Each HTML attribute is an attribute node

Comments are comment nodes

HTML DOM node example

<html>
  <head>
    <meta charset="utf-8">
    <title>DOM 教程</title>
  </head>
  <body>
    <h1>DOM 课程1</h1>
    <p>Hello world!</p>
  </body>
</html>

From the HTML above: The

<html> node has no parent; it is the root node

<head> and <body>'s parent is < html> node

The parent node of the text node "Hello world!" is the<p> node

and:

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

<head> nodes have two child nodes: the <meta> and <title> nodes

<title> node also has one child node : Text node "DOM Tutorial"

<h1> and <p> nodes are sibling nodes and are also child nodes of <body>

And:

The <head> element is the first child node of the <html> element

<body> The element is the last child node of the <html> element

<h1> The element is< The ;body> element's first child node

<p> element is the last child node of the <body> element