Phonetics is the study of the sounds and phenomena associated with human speech. It encompasses various elements, including the formation and pronunciation of sounds. One specific area of interest within phonetics is diphthongs.
According to Oxford: diphthong is a sound formed by the combination of two vowels in a single syllable, in which the sound begins as one vowel and moves towards another
For instance: coin, loud, and side
What is a diphthong?
Phonetics
Diphthongs
What is phonetics?
According to merriam-webster: it is representing the sounds and other phenomena of speech.