Document Object Model
Document :
When an HTML document is loaded into a web browser, it becomes a document object.
Each web page loaded in the browser has its own document object. The Document interface serves as an entry point into the web page's content (the DOM tree, including elements such as <body> and <table>) and provides functionality which is global to the document (such as obtaining the page's URL and creating new elements in the document).
Document Object Model :
The Document Object Model (DOM) is the container for all HTML HEAD and BODY objects associated within the HTML tags of an HTML document.
It is a programming interface for HTML, XML and SVG documents.It provides a structured representation of the document (a tree) and it defines a way that the structure can be accessed from programs so that they can change the document structure, style and content. The DOM provides a representation of the document as a structured group of nodes and objects that have properties and methods. Nodes can also have event handlers attached to them, and once that event is triggered the event handlers get executed. Essentially, it connects web pages to scripts or programming languages.
A Web page is a document. This document can be either displayed in the browser window, or as the HTML source. But it is the same document in both cases. The Document Object Model (DOM) provides another way to represent, store and manipulate that same document. The DOM is a fully object-oriented representation of the web page, and it can be modified with a scripting language such as JavaScript.