Operators accept customer orders. If items aren't in stock or on order, the customer is informed that there will be a 3 week waiting period. If the customer agrees, the missing items will be ordered. Redo warehouse problem using SADTs. SADT attempts to model the control, or actions, rather than the data transformations.
Most techniques rely on stepwise refinement of the model.
All techniques expect an accompanying data dictionary to verbally explain the labels on the diagrams. There are techniques for measuring the quality of the interface. Display techniques are textual, menus, metaphors, icons, graphical . Design issues common to all display techniques are response time, command labeling, transitional user, color, motion, help, error messages .