ACCENT
Accent is the way in which someone pronounces words, influenced by the country or area they come from, or their social class. So, if a dialect deals with, let's say, grammar and vocabulary of a language, then an accent is about pronunciation, phonology of a language. An accent depends on a person's nationality, native language, social class and some other things.
For example, a person who is from Spain speaks English. He/she can speak English with Spanish accent because some of the sounds can still be pronounced in a "Spanish way". A perfect example of accents maybe will be American English, British English and Australian English.
Remember, an accent is a part of a dialect. An accent is always about a specific way of pronunciation.