It is the part of the language system that has to do with the sounds of a given language. Phonetics is a complex and fascinating field of second language acquisition (and linguistics in general). It is often neglected and very often the results are rather obscure to understand for the laymen. Phonetics includes both intonation and pronunciation, which parts of the phonetic structure of a language. We at LinguaCore have developed a simple (but not simplistic) way to deal with  phonetics: the Phonetic Analysis.