Articulation of vowels and diphthongs

The following picture shows where vowels are formed in the mouth cavity, and describes the articulation of all vowels of the western European languages. The signs representing the phonemes are based on the IPA symbol set.

This picture is intended to give you an impression of the linguistic terms used by phoneticians. (The source of the vowel triangle picture is based on the IPA chart available at https://www.internationalphoneticassociation.org/content/full-ipa-chart.)

Most languages have not only vowels but also diphthongs. Diphthongs can be loosely described as a sequence of two single vowels (monophthongs), produced by gliding the position of the first vowel in the direction of the second vowel. For example:

/aU/ in house