Definition
Document Object Model (DOM)
The DOM is the tree-like, object-oriented representation of an HTML page maintained by the browser (living standard by WHATWG). Scripts interact with it through properties (
document.forms,document.links, …) and methods (document.createElement,document.getElementsByTagName, …) to read and modify the page content.The DOM is what JavaScript manipulates, and a script running on an origin gets full read/write access to that origin’s DOM — which is exactly what makes XSS dangerous.