The box which should be used as outline for the page.
The dimensions of the intersection of the media box and the crop box. If the crop box is not present, the visible box is set to the media box.
The boundaries of the physical medium on which the page is intended to be displayed or printed.
The visible region. When the page is displayed or printed, its contents are to be clipped (cropped).
The region to which the contents of the page should be clipped when output in a production environment.
The intended dimensions of the finished page after trimming.
The extent of the page's meaningful content (including potential white space) as intended by the page�s creator.