This chapter provides information to functional triad, which is a conceptual framework that illustrates the three roles computing technology can play—tool, media, and social actor. These three functions capture how people use or respond to virtually any computing product, from simple products such as a portable electronic pedometer to sophisticated products such as such as TurboTax for the Web. The chapter also provides an overview of these three key elements of the functional triad. In functioning as tools, computers can influence people in a number of ways; they can make a target behavior easier to perform, lead users through a process, or perform calculations or measurements that motivate. When functioning as sensory media, computing technology can persuade people by providing compelling experiences through simulations. When computing products adopt the role of social actor, they persuade people by applying the same persuasion principles that humans use to influence others; as social actors, computers can persuade people to change their attitudes or behaviors by rewarding them with positive feedback, modeling a target behavior or attitude, or providing social support.