There are also differences in Grammar and vocabulary .I would overdo if I said that what in a place can be hilarious , some miles away can trigger a riot , it is not that exaggerate , but differences exist.
Social and situational factors affect language and make it vary. When we speak to a person we can identify some features such as origen or even social status. This is called variation , and variation affects both our situational background and , consciously , the way we react to someone speech or in order to adhere to certain social class.
There are terms which are worthy of mention : Accent and dialect.
Dialect is a language variety distinguished from other varieties by gramar and vocabulary . Standard British English is a dialect ,as are Scottish , American or Black English Vernacular.
Accent has to do with differences in pronounciation what means just a charactistic combination of phonetic features which we connect with a particular geographical area o social background.It is a well -known fact that RP ( Received Pronuntiation ) or Standard Southern British English is ,nowadays, a symbol of prestigie and it is related to upper classes , the accent of those educated in public schools and those with high incomes.
It is not my intention to entry in the complicated field of Sociolinguisics but just emphasize the fact that a particular accent can devalue or overrate someone since it is associated to a certain status , low or high instead of paying atention to the differents changes in pronunciation and what is even more important,that English , as all living languages, change over the time, it is in constant flux because people use them endlessly.
RP is not regional or local accent but the accent that is widely regarded as symbol or correctness, and unfortunately , some people pretending to be someone more whealthy ,or educated tent to imitate it, creating just affectation.
Arthur Huhges: "English accents and dialects"