A JavaScript window is a complex object. It must keep
track of context in various ways. Pointers keep track of a window's place within the
navigator hierarchy. Each window contains pointers to :
Its parent, the window which owns it;
Its topmost ancestor (top); and
Its self.
Windows store a list of subframes (frames) to track dependents.
Additionally:
The history array remembers previous URLs;
The location points to the current URL; and
The document stores information
about the presentation and content of the current page.
Please refer
to the communications overview for
further information about document methods. The
Window Inspector gives an excellent
hands-on approach to understanding window structures. The JavaScript
window hierarchy looks something like this: