Chapter 1 – Scenario-Based Usability Engineering

Publisher Summary This chapter discusses the problems in software development that motivate the use of scenario-based development methods. It also provides an overview of the scenario-based framework that forms the basis for the rest of the book, and the case study that will be used to illustrate the techniques. The challenges and methods that have contributed to modern software engineering practices have been reviewed. Usability emerged as an issue when the population of end users and the situations in which computing was used expanded from specialty to general-purpose use. It can be seen as a union of three perspectives: the human factors of perception and performance; the cognitive interactions of humans and computers; and the groups and organizations that provide the context for personal computing. Scenarios are concrete descriptions of action that are rough and flexible in content and level of abstraction. These characteristics help usability engineers address a number of fundamental tradeoffs in the design and development of usable systems. Scenarios integrate the many tasks of system development by first organizing the analysis of user needs, then serving as central representations of user needs that are developed in a systematic manner through design, evaluation, and documentation activities. An example of scenario-based design is provided, shifting to a historical survey of issues in software and usability engineering. This chapter concludes with a discussion of the major phases and methods employed in scenario-based development.