> For the complete documentation index, see [llms.txt](https://bharat-tiwari.gitbook.io/our-tech-journal/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://bharat-tiwari.gitbook.io/our-tech-journal/javascript/window-document-screen.md).

# window, document, screen

`window` is the main JavaScript object root, aka the `global object` in a browser, and it can also be treated as the root of the document object model. You can access it as `window`.

`window.screen` or just `screen` is a small information object about physical screen dimensions.

`window.document` or just `document` is the main object of the potentially visible (or better yet: rendered) document object model/DOM.

*Since `window` is the global object, you can reference any properties of it with just the property name - so you do not have to write down `window.` - it will be figured out by the runtime.*

*(*[*source: stackoverflow*](https://stackoverflow.com/a/9895261)*)*