Window.window Property---the window itself
Navigator 2.0, Internet Explorer 3.0
window.window
The window property is identical to the self property; it contains a reference to the Window object specified by window. That is, window.window is identical to window itself. Because a reference to the current top-level window or frame is implicit in all JavaScript expressions, the window in the above expressions can be omitted and you can simply use window to refer to the current window.
The window property (and its synonym, self) provides a way to explicitly refer to the current window or frame when necessary, or when convenient for code clarity. To open a new window in an event handler, for example, it is necessary to use window.open(), because open() by itself would be confused with the Document.open() method.
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