Examples of DIALECTS are Standard English (SE, the language this page is written in), Lowland Scottish, Cockney, Black English - we look at these and other varieties in 05.15.33 Dialects.
Every dialect has its own accent - Scots is usually spoken with a Scottish accent, Cockney with a London accent. Standard English is generally associated with RP, but is more often spoken with varying degrees of regional accent:
SE is spoken and and written all over the world. It varies slightly in different countries - Scotland, Ireland, USA, Australia, etc., but these varieties are all very superficial indeed - a few words spelt differently, a few small grammatical differences. Written accademic English is on the whole the same all over the world. A very large amount of written academic or scientific or business English is written by people who have learnt English as a foreign language.
Most of the major languages of the national languages of the world have a STANDARD dialect which most people consider to be the "correct" way of writing and speaking. When we talk of English, French, Russian or Vietnamese, we are usually refering to Standard English, Standard French, Standard Russian and Standard Vietnamese. The standard dialect of any language is the one which is written, taught in schools, and has a generally higher prestige than other dialects.
But most languages also have a range of REGIONAL dialects with different rules of gemmar and a different vocabulary. We can call these NON-STANDARD dialects, but we must remember that this does not imply that they are linguistically inferior to the standard dialects, and we must avoid thinking of them as SUB-STANDARD forms of the language.
In Standard English, one could say "I haven't got any change".
In a non-standard dialect, this sentence might be, "I ain't got no change".
Both these sentence are grammatically correct, but the rules of grammar differ between dialects. If you write "I ain't got no change" and your teacher marks it wrong, just remember that your teacher expected you to write in Standard English and not to switch dialects without some good reason.
If you have any questions mail me at firstname.lastname@example.org.