Window — a web browser window, tab, or frame

Inherits from



The Window object represents a browser window, tab, or frame. It is documented in detail in Chapter 14. In client-side JavaScript, the Window serves as the “global object,” and all expressions are evaluated in the context of the current Window object. This means that no special syntax is required to refer to the current window, and you can use the properties of that window object as if they were global variables. For example, you can write document rather than window.document. Similarly, you can use the methods of the current window object as if they were functions: e.g., alert() instead of window.alert().

Some of the properties and methods of this object actually query or manipulate the browser window in some way. Others are defined here simply because this is the global object. In addition to the properties and methods listed here, the Window object also implements all the global properties and functions defined by core JavaScript. See Global in Part III for details.

Web browsers fire many kinds of events at windows. This means that the Window object defines quite a few event handlers, and that Window objects implement the methods defined by EventTarget.

The Window object has window and self properties that refer to the window object itself. You can use these to make the current window reference explicit rather than implicit.

A Window can contain other Window objects, typically in the form of <iframe> ...

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