Phonetic transcription (also known as Phonetic script or Phonetic notation) is the visual representation of speech sounds (or phonetics) by means of symbols. The most common type of phonetic transcription uses a phonetic alphabet, such as the International Phonetic Alphabet.
Americanist phonetic notation, also known as the North American Phonetic Alphabet (NAPA), the Americanist Phonetic Alphabet or the American Phonetic Alphabet (APA), is a system of phonetic notation originally developed by European and American anthropologists and language scientists (many of whom were Neogrammarians) for the phonetic and phonemic transcription of indigenous languages of the Americas and for languages of Europe. It is still commonly used by linguists working on, among others, Slavic, Uralic, Semitic languages and for the languages of the Caucasus, of India, and of much of Africa; however, Uralicists commonly use a variant known as the Uralic Phonetic Alphabet.
Despite its name, NAPA has always been widely used outside the Americas. For example, a version of it is the standard for the transcription of Arabic in articles published in the Zeitschrift der Deutschen Morgenländischen Gesellschaft, the journal of the German Oriental Society.
The International Phonetic Alphabet (IPA) is an alphabetic system of phonetic notation based primarily on the Latin script. It was devised by the International Phonetic Association in the late 19th century as a standard written representation for the sounds of speech. The IPA is used by linguists, lexicographers, foreign language students and teachers, speech–language pathologists, singers, actors, constructed language creators, and translators.
The IPA is designed to represent those qualities of speech that are part of lexical (and, to a limited extent, prosodic) sounds in spoken (oral) language: phones, intonation and the separation of syllables. To represent additional qualities of speech – such as tooth gnashing, lisping, and sounds made with a cleft palate – an extended set of symbols may be used.
A phonological rule is a formal way of expressing a systematic phonological or morphophonological process in linguistics. Phonological rules are commonly used in generative phonology as a notation to capture sound-related operations and computations the human brain performs when producing or comprehending spoken language. They may use phonetic notation or distinctive features or both.
John Goldsmith (1995) defines phonological rules as mappings between two different levels of sounds representation—in this case, the abstract or underlying level and the surface level—and Bruce Hayes (2009) describes them as "generalizations" about the different ways a sound can be pronounced in different environments. That is to say, phonological rules describe how a speaker goes from the abstract representation stored in their brain, to the actual sound they articulate when they speak. In general, phonological rules start with the underlying representation of a sound (the phoneme that is stored in the speaker's mind) and yield the final surface form, or what the speaker actually pronounces. When an underlying form has multiple surface forms, this is often referred to as allophony. For example, the English plural written -s may be pronounced as [s] (in "cats"), [z] (in "cabs", "peas"), or as [əz] (in "buses"); these forms are all theorized to be stored mentally as the same -s, but the surface pronunciations are derived through a series of phonological rules.