ABSTRACT
This chapter discusses terminology; enumerate some common properties of input devices and provides examples of how these properties apply to familiar examples of devices such as touch screens, pens, and mice. It describes state-transition models of devices and how these relate to interactive techniques, as well as the hierarchies of fundamental tasks that delineate the units of interaction in a user interface. The chapter examines a number of models and theories that are commonly used to evaluate human performance with interaction techniques and devices. It aims to treat input technologies at the level of interaction techniques, which provide a way for users to accomplish tasks by combining input with appropriate feedback. A designer who understands input technologies and the task requirements of users has a better chance of designing interaction techniques that match a user's natural workflow and that take appropriate advantage of a user's innate abilities.
