Speech is human, silence is devine, et also brutish and dead; therefore we must learn both arts.
Thomas Carlyle
Phonology is the study of telephone etiquette.
A high school student
Linguists are interested in how sound systems may vary, and in the ways they are similar, in the phonetic and phonological universals found in all languages. The same relatively small set of phonetic properties or features characterises all human speech sounds; the same classes of these sounds are utilised in languages spoken from the Arctic Circle to the Cape of Good Hope, and the same kinds of regular patterns of speech sounds occur in your language and how they pattern according to regular rules.
Phonology is concerned with this kind of linguistic knowledge. Phonetics is a part pf phonology, and provides the means for describing speech sounds; phonology is concerned with the ways in which these speech sounds form systems and patterns in human language. Phonology, like grammar, is used in two ways the mental representation of linguistic knowledge and the description of this knowledge. Thus the word phonology refers either to the representation of the sounds and sound patterns in a speaker's grammar, or to the study of the sound patterns in a language or in humman language in general.
Phonological knowledge permits a speaker to produce sounds which form meaningful utterances, to recognise a foreign 'accent', to make up new words, to add the appropriate phonetic segments to form plurals and past tenses, to produce 'aspirated' and 'unaspirated' voiceless stops in the appropriate context, to know what is or is not a sound in his or her language, and to know that different phonetic strings may represent the same morpheme.
