There are three main branches of phonetics:

i) Articulary Phonetics

ii) Acoustic Phonetics

iii) Auditory Phonetics

Articulatory, acoustic, auditory

Phonetics is the science studying the sounds of speech: it is all about the way you say things (articulatory phonetics), hear things (acoustic phonetics) and perceive what you hear (auditory phonetics).

Studies in phonetics become increasingly important today, as they are central to speech recognition technology.

Phonetics is a study of speech sound. Acoustic phonetics is a sub-sector of it. Acoustic phonetics is a study of physical aspects of speech sounds. Speech goes away as the speech sounds come out of your mouth unless you record the speech. Thus, we record speech sounds for analysis. Acoustic phonetics includes study of fundamental frequency (pitch), amplitude/intensity (loudness), duration (length), formant estimates, and other physical aspects of speech sounds.

Axel Koberne has written:

'Neutralisierbare Akzentoppositionen in der Vorkontur' -- subject- s -: Accents and accentuation, Acoustic Phonetics, English language, Intonation, Intonation - Phonetics -