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JS Objects
Object Definitions Object Properties Object Methods Object Constructors Object Prototypes
JS Functions
Function Definitions Function Parameters Function Call Function Apply Function Closures
JS HTML DOM
DOM Introduction DOM Methods DOM Selectors DOM HTML DOM CSS DOM Attributes DOM Navigation
JS Browser BOM
JS - Window JS - Screen JS - Location JS - History JS - Navigator JS - Popup Alert JS - Timing JS - Cookies
JS AJAX
AJAX - Introduction AJAX - XMLHttp AJAX - Request AJAX - Response AJAX - PHP
JS JSON
JSON - Introduction JSON - Syntax JSON - Data Types JSON - Parse JSON - Stringify JSON - Objects JSON - Arrays JSON - PHP JSON - JSONP
JS References
JavaScript Reference JavaScript Methods HTML DOM Reference

JavaScript HTML DOM

The Document Object Model, usually referred to as the DOM, is an essential part of making websites interactive.

The Document Object Model represents the HTML document that is displayed in a window.

It is an interface that allows JavaScript to manipulate the content, structure, and style of a website.


The HTML DOM (Document Object Model)

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.

Below is an example that explains what is DOM:

The DOM represents of above code is like this:

HTML DOM

DOM representation of above example

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

In other words: The HTML DOM is a standard for how to get, change, add, or delete HTML elements.


DOM and JavaScript

With the object model, JavaScript gets all the power it needs to create dynamic HTML:

  • JavaScript can change all the HTML elements in the page
  • JavaScript can change all the HTML attributes in the page
  • JavaScript can change all the CSS styles in the page
  • JavaScript can remove existing HTML elements and attributes
  • JavaScript can add new HTML elements and attributes
  • JavaScript can react to all existing HTML events in the page
  • JavaScript can create new HTML events in the page

What You Will Learn

In the next chapters of this tutorial you will learn:

  • How to find HTML elements
  • How to change the content of HTML elements
  • How to add and delete HTML elements
  • How to change the style (CSS) of HTML elements
  • How to add and remove HTML Attributes
  • How to navigate DOM tree