Very interesting question Abd...hopefully I can answer this in a simple way: (starting from most difference to least) Language --> Dialect --> Accent Language = What we use to communicate to one another. Many European languages (such as French/Spanish/Portuguese/Italian) have Latin origins but are now their own system of communication. Dialect = Is a variety of language that is spoken in a specific region or by particular group of people that has direct origins to the original language. It often has different vocabulary/grammar/pronunciation. Accent = Is generally just a way of pronouncing a language. This can again occur within different regions or groups but there isn't a change of syntax that is seen with language or vocabulary. Hope this helps!

Here's an example: Your first language is Arabic. You also know two other languages: English and French. Hundreds of millions of people speak Arabic as their first language, but they speak different variants of Arabic, for example Gulf Arabic and Levantine Arabic. Pronunciation, grammar and vocabulary vary from one dialect to another. Sometimes dialects of the same language are mutually comprehensible, sometimes they aren't. An accent is only about the way someone sounds when they speak: pronunciation, and also other features such as stress and intonation. For example, when you speak English, you speak with an Arabic accent: this means that you 'sound' Arabic, even when using English words and grammar. If I were to learn Arabic and speak to you, I'd speak with an English accent. An Egyptian man living in Algeria might sound Egyptian to your ear, even when he is speaking Algerian Arabic to you. I hope that helps.