Dialogue system – Wikipedia
A dialogue system, or conversational agent (CA), is a computer system intended to converse with a human with a coherent structure. Dialogue systems have employed text, speech, graphics, haptics, gestures, and other modes for communication on both the input and output channel.
What does and does not constitute a dialogue system may be debatable. The typical GUIwizard does engage in some sort of dialog, but it includes very few of the common dialogue system components, and dialog state is trivial.