The Document Object Model (DOM) is a programming interface that allows scripts to access and manipulate the structure, style, and content of a web document. It represents the document as a tree of objects, where each node corresponds to a part of the document, such as elements, attributes, and text. This model enables developers to dynamically change the document's content and structure using languages like JavaScript. The DOM is essential for creating interactive web applications, as it allows for real-time updates without needing to reload the entire page. By using the DOM, developers can respond to user actions, modify styles, and add or remove elements, enhancing the overall user experience on websites.