Summary
The Document Object Model (DOM) exists to allow for interaction with the webpage using code. Technically, you could write an HTML/CSS page without needing the DOM, but as soon as you want to add anything in a scripting language, the DOM becomes the only way to make that connection. Using the DOM, a multitude of pre-written methods are accessible, which relates to what Visual Studio provides for other languages. The DOM has great functionality, but in order to be able to use it in the first place, someone has to maintain it. Originally, the W3C solely handled the specifications, and they are still involved in keeping people up to date, but WHATWG is now the main handler. As mentioned before, a web page doesn't need the DOM for HTML/CSS rendering, so the browser treats it as a separate collection of elements. In addition, browsers allow access to themselves through the DOM as well. Window elements access the browser itself; document objects access the web page. Overall, without the DOM, web pages would not nearly be as advanced as they are today.