Bridging the Generation Gap: From Work Tasks to User Interface Designs

Task and model-based design techniques support the design of interactive systems by focusing on the use of integrated modelling notations to support design at various levels of abstraction. However, they are less concerned with examining the nature of the design activities that progress the design from one level of abstraction to another. This paper examines the distinctions between task and model-based approaches. Further, it discusses the role of design activities in such approaches, based on experience with one task-based technique, and the resulting implications for tool support and design guidelines. The discussion is contextualised by examples drawn from a number of case studies where designers applied a task-based approach to solve one particular design problem: that of developing an airline flight query and booking system.