The object returned by this property is shared by all windows, since there is only one Screen object for the entire browser.
Refer to the Screen object topic for details of how you can examine its properties. There are some minor differences between MSIE and Netscape Navigator regarding the properties that their Screen objects support.
The WebTV box yields an object that describes the properties of a device that operates at TV display resolution.
This may not behave the same on all platform configurations. Consider the possibility of having several monitor screens. Some OS platforms insist on all screens being the same size and resolution in which case a single Screen object will suffice.
In the case of the Macintosh Operating System, you may have several screens, each of which can be a different size, orientation and color depth. Indeed, you can even mix monochrome and color screens. One will be the main screen by virtue of it having the menubar placed on it. The screens can be positioned relative to one another in any orientation.
So for an OS such as Mac OS, a single Screen object may not suffice. However, the browser manufacturers may not fully support this. You will need to test this if it is important to your application. It is possible there will still be a single Screen object and that it will represent the master screen. However it might represent the screen that the window is positioned on.
The Macintosh OS is somewhat unique in that a window may span several screen displays. This would make it difficult for any Screen object (or even several) to accurately represent the real world.