The ConcurTaskTrees Notation

Two research streams have affected the design and development of ConcurTaskTrees: model-based user interface design and formal methods for human-computer interaction. The main purpose of this notation is to support the specification of flexible and expressive task models that can be easily interpreted even by people without formal background. Such representations can be useful for designers in the various phases of the design cycle and can be used for both prescriptive and descriptive purposes.