An accent is heard when pronouncing the same text.

A dialect is a language variety which has different words and grammars.

You might be interested in this Dialect Map of American English, though the author doesn't seem to follow his own advice and often explains dialects by accents.

The term, accent, is often incorrectly used in its place, but an accent refers only to the way words are pronounced, while a dialect has its own grammar, vocabulary, syntax, and common expressions as well as pronunciation rules that make it unique from other dialects of the same language.

Unfortunately the word "dialect" is of political importance since the French Revolution invented the nation state and is emotionally overloaded.

From a linguistic perspective do all Dutch, German, Afrikaans and Yiddish dialects belong to the same dialect continuum, like Portuguese, Castilian, Catalan, Occitan French, "proper" French and Italian do.

Making this statement too carelessly will at best end you up in a pub fight, at worst start a war.

> for radio and television

the Sunday sermon had this function in medieval days

I have to say I really love dialects and accents and I consider them part of high culture!

But I wouldn't object if some key figures of the Perl community would bother to be understood at conferences.