Until recently, the World Wide Web has relied exclusively on visual interfaces to deliver information and services to users via computers equipped with a monitor, keyboard, and pointing device. In doing so, a huge potential customer base has been ignored: people who (due to time, location, and/or cost constraints) do not have access to a computer.
Many of these people do, however, have access to a telephone. Providing “conversational access” (that is, spoken input and audio output over a telephone) to Web-based data will permit companies to reach this untapped market. Users benefit from the convenience of using the mobile Internet for self-service transactions, while companies enjoy the Web's relatively low transaction costs. And, unlike applications that rely on dual tone multi-frequency (DTMF) input (telephone keypress), voice applications can be used in a hands-free or eyes-free environment, as well as by customers with rotary pulse telephone service or telephones in which the keypad is on the handset.