reates a new window, but doesn't display
    it. Before it shows up on the screen we must initialize it with
    some appropriate values. For that, we'll use the
    method <code>initWithContentRect:styleMask:backing:defer:</code>.</p>

    <p>As always in Objective-C, the name of the method reveals
    something about the arguments it expects. The <code>NSRect</code>
    that we pass for the <code>initWithContentRect:</code> segment of
    the method name describes the shape of the window. The mask
    for