Natural language is a pervasive speech technology that has found its way into current applications. It may eventually have a profound impact on both speech recognition and synthesis. This technology can be used for both input and output. Because of the multi-disciplinary community involved in speech user interface development, the term natural language has several connotations.
From a linguistic standpoint, a natural language is the language spoken and written by a given culture. Therefore, English, French, Italian, Spanish, German, Japanese, and Chinese are all natural languages. All facets of linguistic analysis apply to a natural language. It can be discussed in terms of its phonological, grammatical, semantic, and pragmatic characteristics. From an interaction standpoint, the speech user interface designer is particularly interested in a pragmatic analysis. We are concerned with how people use language in an everyday manner and how that usage can be applied to controlling a computer. We also seek to build a computer that responds consistently under a variety of circumstances.
In the computing community, natural language implies an alternative to other modes of interaction, such as command languages.
It is common to use special, or artificial, languages to facilitate communication in specific fields and aid problem solving. For example, notational languages are used for mathematics, music, and chemistry. Computer programming languages follow a similar model. ...