When a web page is loaded, the browser creates a Document Object Model of the page.
The HTML DOM model is constructed as a tree of Objects:
What is DOM
Document Object Model (DOM) is a platform and language-neutral interface that allows programs and scripts to dynamically access and update the content, structure, and style of a document.
The W3C DOM standard is separated into 3 different parts:
Core DOM - standard model for all document types
XML DOM - standard model for XML documents
HTML DOM - standard model for HTML documents
What is the HTML DOM?
The HTML DOM is a standard object model and programming interface for HTML. It defines:
The HTML elements as objects
The properties of all HTML elements
The methods to access all HTML elements
The events for all HTML elements
With the object model, JavaScript gets all the power it needs to create dynamic HTML:
1. JavaScript can change all the HTML elements in the page