HTMLDocument
For historical reasons, Window objects have a window.HTMLDocument property whose value is the Document interface. So you can think of HTMLDocument as an alias for Document, and you can find documentation for HTMLDocument members under the documentation for the Document interface.
Properties
Returns the deepest element in the document through which or to which key events are being routed. This is, roughly speaking, the focused element in the document.
The Document.body property represents the or node of the current document, or null if no such element exists.
node is a CDATASection node.
The Document.characterSet read-only property returns the character encoding of the document that it's currently rendered with.
The read-only childNodes property of the Node interface returns a live NodeList of child nodes of the given element where the first child node is assigned index 0. Child nodes include elements, text and comments.
Returns the child elements.
node is a Comment node.
The Document.compatMode read-only property indicates whether the document is rendered in Quirks mode or Standards mode.
The Document.contentType read-only property returns the MIME type that the document is being rendered as. This may come from HTTP headers or other sources of MIME information, and might be affected by automatic type conversions performed by either the browser or extensions.
The Document.currentScript property returns the