Phonology is a field of linguistics, the study of language, the goal of which is to understand the vocal and auditory structure of human speech. While different languages may sound distinctly different, all humans have the same physiological brain, ear, and vocalization apparatuses. Spoken language is the patterned interaction of these three links. Applications of this field of study extend to a broad variety of disciplines and professions for which effective speech and communication is essential. It is used for political purposes, to help teach foreign languages, and in the development of computer language processing, among other applications.
In years past, phonology was mainly theoretical and academic. It remains vitally so, but is especially important for the linguistic research and analysis, and the preservation of historically dying or extinct languages. Many modern governments have national interest in, and institutions for, retaining the undiluted integrity of their mother tongue. These applications may involve the areas of history, political science, and sociology.
The teaching of a foreign language benefits from a scientific understanding of how human vocal sounds are created and sequenced to correctly form the words and sentences that convey meaning. Actors hire phonology experts to develop convincing accents; some professionals may use one to lose a foreign accent. In certain global industries, such as aviation, English is the official lingua franca; there is need for capable teachers throughout the world. Likewise, global migration has created a local need to teach immigrants the language of their newly adopted home country.
In the United States and elsewhere around the world, the education of children has been extended by law to include those who have learning difficulties or other special needs. Most schools are staffed by a dedicated or contracted audiologist to evaluate students' hearing ability and a speech therapist to assist students' communication skill. The same help extends to adults suffering from a speech disorder or rehabilitating from brain injury. An understanding of phonology can be an important asset in these fields.
It is not surprising that most commercial businesses need to employ insightful linguists to communicate with the marketplace. Media companies, advertising firms, and any other company which relies on the spoken word must evaluate and optimize both the message and its delivery. Even industries such as publishing, which are primarily involved in the written language, have a need for people knowledgeable in phonology. Applications of phonology also enter professional sectors, such as forensic voice analyses in law enforcement.
One of the most important applications of phonology is in the computer sciences. Accurate speech recognition and fluid speech synthesis require a detailed understanding of how the sounds of language are generated, structured, and subsequently parsed into discreet meanings. The computer-human interaction, whether it be an automated transaction system or a smart phone interface, increasingly includes voice. A computer will have one day passed the so-called "Turing Test" for artificial intelligence, and the next test will require the computer to speak with convincing intelligence. Advances in computational linguistics and natural language processing may also lead to a universal translator.