ABSTRACT
Numerous advances have been made in identifying the kinds of knowledge relevant to informing the design of graphical interfaces for complex tasks that inquire into the nature of the user, task, problem and representation. Four levels of information underpin the relational structure of a system: the global reference structures; attributes; relations and interrelations. For any model of a system, types of relational and interrelational structures subsume types of the elementary structure. This is because interrelational and relational structures are composed of the elementary constituents of the model. Designing representations that intrinsically encode the elementary structure of a system is particularly useful when it is problematic to specify all the kinds of information required for a task. Although the representation is not guaranteed to be the best for every task it will typically have greater task generality than more abstract information displays that were designed to match specific tasks.
