It becomes possible, for example, to query a link, but to go on reading while simultaneously learning more about the size, availability, type, and content pointed to by the link. As users of The Audible Web, we find that the constant low level audio feedback for user actions as well as link events and attributes creates a ubiquitous audio environment, in which sounds are an expected part of interactions rather than a surprise or salient special event. This preliminary experience suggests further study is needed to understand how human-computer interactions are affected by environments in which audio is truly ubiquitous. Naturally, there are many purposes for which audio is not well suited. Users can acquire an abstract sense of file size from audio cues, for example, but if they need to know that one file is 1.2 megabytes while another is 1.4 megabytes, non-speech audio may not provide the information they need.
More work is needed to determine when and where audio is an appropriate interface element.
The Audible Web prototype suggests a host of research questions about the use of audio in applications. In future research, we must validate users' understanding of auditory cues, study the effectiveness of audio for enhancing user-interface interactions, and determine users acceptance of audio cues. We would like to thank the members of HCI, COCO, and other groups at SunSoft for their help and support during Mike's summer internship. Delivery of Information Through Sound . Addison-Wesley Publishing Company.