DOM

A programming interface that represents an HTML or XML document as a tree structure of objects, where each node corresponds to a part of the document such as elements, attributes, and text content. The DOM is critical to accessibility because assistive technologies like screen readers build their own representation of page content from the DOM and its associated accessibility tree. When JavaScript modifies the DOM dynamically — as in single page applications — these changes must be communicated to assistive technologies through proper use of ARIA live regions, focus management, and semantic HTML to ensure all users are aware of content updates.