28. The apparatus of claim 27 wherein said editor program is structured to control said computer to make said dialog for designing user interfaces for classes context sensitive such that it has a left pane in which the elements of said Conceptual Model are shown, and when said designer selects an element shown in said left pane, and selects an icon or menu choice to add a user interface pattern, only the user interface patterns that can be added to the selected element of said Conceptual Model are shown in another pane or a completely separate dialog referred to as a listbox, and wherein said editor program is structured to respond to selection of a pattern from said listbox and selection of a button displayed on said listbox indicating the desire of said designer to add said pattern by adding said pattern to said Presentation Model.
28. The apparatus of claim 27 wherein said editor program is structured to control said computer to make said dialog for designing user interfaces for classes context sensitive such that it has a left pane in which the elements of said Conceptual Model are shown, and when said designer selects an element shown in said left pane, and selects an icon or menu choice to add a user interface pattern, only the user interface patterns that can be added to the selected element of said Conceptual Model are shown in another pane or a completely separate dialog referred to as a listbox, and wherein said editor program is structured to respond to selection of a pattern from said listbox and selection of a button displayed on said listbox indicating the desire of said designer to add said pattern by adding said pattern to said Presentation Model. 29. The apparatus of claim 28 wherein said editor program is structured to control said computer to display a definition tab on said dialog box for designing user interfaces for classes which, when selected, causes a new dialog to open which provides said designer lists of elemental patterns that can be selected by said designer and used to articulate an interaction unit pattern said designer has selected, and wherein said editor program is structured control said computer to display buttons said designer can use to add or delete elemental patterns said designer has selected from said displayed lists so as to articulate said selected interaction unit, and when an add button has been selected, the selected elemental pattern is shown in a pane which will be referred to as the selected pane and which is a different pane from the pane in which said elemental pattern was listed and selected from, and wherein said editor program is also structured to control said computer to display an edit button associated with said selected pane, which when selected opens a dialog which allows information to be entered to define attributes of said selected elemental pattern.