Task Models and Diagrams for User Interface Design
Task analysis and modelling have existed for many years, initially for tra- ing purposes but latterly for providing a principled approach to improving the usability of existing and proposed interactive systems. There have been many successesalongwith criticalappraisalofthe utility oftask analysis.Thecom- nity remainsstrong, activeand enthusiastic. Over the yearswehavedeveloped a plethora of theoretical approaches,models and techniques. These di?er in terms of what is modelled, the nature of the representations and notations used, their scalability, the ease with which they can be applied with good e?ect, and the ease with which they can direct the design of systems to support task execution. Task models and associated diagrams that represent task knowledge and behavior are in demand now as much as they ever were. Good design is f- damental, appreciated by users, sells and improves the quality of our daily lives, and good system design means supporting users and their interaction with technology. Technology is changing – we now have mobile and pervasive systems – and yet we still need to analyze the goals and tasks undertaken using these systems. The nature of the tasks might be di?erent (shorter in duration, overlapping,needing to be performed more quickly, be routed in communication and entertainment), but it is still important to understand, model and support user goals.