Input Technologies and Techniques (2012)

The barometer has fallen and a brisk wind blows. Input and interaction is not what it used to be.

The gusts drift over the line in the sand that separates input from output. The academic division between input and output as topics of study was never a principled one to begin with. But this is perhaps clearer now than ever before: many people now primarily experience computing by direct-touch input on their displays. The shifting sands are rapidly unearthing a future where any surface on which we can display information will also serve as a surface that sees, hears, feels, and otherwise senses all of our interactions. As some would have it, the encroaching dunes have all but buried the mouse, keyboard and other indirect input devices as archeological curiosities, to be unearthed by a future generation of researchers, explorers, and scoundrels.

What is the prospector of innovative devices and interaction techniques to make of this new landscape? Is it a desert or is it an oasis? In our view it is a little bit of each. Everyone is now familiar with multi-touch as the defining example of direct interaction, but it is not the whole story. As our colleague Bill Buxton constantly likes to remind us, a key lesson to remember is the following: Everything, including touch, is best for something and worst for something else. The goal for this chapter is to help you understand why, how, and under what circumstances, by way of a survey of illustrative examples, devices, techniques, and conceptual tools. It will also help you understand why direct interaction is about much more than just multi-touch. Direct interaction not only includes many variations on touch itself, but also includes modalities such as pen input,

Everything, including touch, is best for something and worst for something else.

The goal for this chapter is to help you understand why, how, and under what circumstances, by way of a survey of illustrative examples, devices, techniques, and conceptual tools. It will also help you understand why direct interaction is about much more than just multi-touch. Direct interaction not only includes many variations on touch itself, but also includes modalities such as pen input, motion and postural sensing, and proximal and spatial interactions in the physical space beyond the display. Each of these in turn exhibits its own idiosyncratic strengths and weaknesses.