A tidy node is a PHP object
Each node is an instance of the internal tidy_node class with the following structure:

The tidy_node class
<?php
class tidy_node {

    public $value;
    public $name;
    public $type;
    public $id;        /* $id Not always available, depends on type */
    
    public tidy_node $child[];
    
    public function hasChildren();
    
    public function isComment();
    public function isHtml();
    public function isText();
    public function isJste();
    public function isAsp();
    public function isPhp();
    
}
?>