Linguists use an approach called lexical sets to talk about vowels
This uses words to stand in for the vowels in those words - e.g 'bath' contains the 'a' sound. This is the same vowel, but pronounced differently.
Regional Dialects
Some accents are more distinctive than others - for instance, algorithms cannot tell accents from Sheffield, Manchester and Leeds apart, but are okay with Liverpool and Newcastle.
A study conducted asked 100 people to listen to audio clips of different accents, locate the speaker, and identify what features gave them this conclusion.
For example, Sheffield speakers were identified by glottal stops and flat vowel sounds, Scouse were identified by the 'ck' sound.