DOM

The DOM represents an XML or an HTML document as a tree of nodes. Using DOM methods and properties, you can access any element on the page, modify or remove elements, or add new ones. The DOM is a language-independent API and can be implemented not only in JavaScript, but also in any other language. For example, you can generate pages on the server-side with PHP's DOM implementation (http://php.net/dom).

Take a look at this example HTML page:

    <!DOCTYPE html> 
    <html> 
      <head> 
        <title>My page</title> 
      </head> 
      <body> 
        <p class="opener">first paragraph</p> 
        <p><em>second</em> paragraph</p> 
        <p id="closer">final</p> 
        <!-- and that's about it --> 
      </body> 
    </html> 

Consider the second paragraph (<p><em>second</em> paragraph</p>). You will see that it's a <p> ...

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