The International Phonetic Alphabet (IPA) can be used to represent sound correspondences among various accents and dialects of the English language.
These charts give a diaphoneme for each sound, followed by its realization in different dialects. The symbols for the diaphonemes are given in bold, followed by their most common phonetic values.
A diphthong (/ˈdɪfθɒŋ, ˈdɪp-/ DIF-thong, DIP-), also known as a gliding vowel or a vowel glide, is a combination of two adjacent vowel sounds within the same syllable. Technically, a diphthong is a vowel with two different targets: that is, the tongue (and/or other parts of the speech apparatus) moves during the pronunciation of the vowel. In most varieties of English, the phrase "no highway cowboys" (/noʊ ˈhaɪweɪ ˈkaʊbɔɪz/ noh HY-way KOW-boyz) has five distinct diphthongs, one in every syllable.
Diphthongs contrast with monophthongs, where the tongue or other speech organs do not move and the syllable contains only a single vowel sound. For instance, in English, the word ah is spoken as a monophthong (/ɑː/), while the word ow is spoken as a diphthong in most varieties (/aʊ/). Where two adjacent vowel sounds occur in different syllables (e.g. in the English word re-elect) the result is described as hiatus, not as a diphthong.