ABSTRACT
Our sense of hearing is very powerful, and we can extract a wealth of information from the pressure waves entering our ears as sound. Sound gives us a continuous, holistic contact with our environments; we hear a rich set of sounds from our interactions with objects close to us, familiar sounds of unseen friends or family nearby, noises of things to avoid, such as traffic, and noises of things to attend to, such as a ringing telephone. Nonspeech sounds (such as music, environmental sounds, and sound effects) give us different types of information than those provided by speech; they can be more general and more ambient where speech is precise and requires more focus (see chapter XXX for more on speech output). Nonspeech sounds complement speech in the same way that visual icons complement text. For example, icons can present information in a small amount of space as compared to text; nonspeech sounds can present information in a small amount of time as compared to speech. There is less research about nonspeech than speech interfaces, and this chapter will show something of where it has been used and of what it is capable.
