Tone is the use of
pitch in
language to distinguish lexical or grammatical meaning – that is, to distinguish or to
inflect words. All verbal languages use pitch to express emotional and other paralinguistic information and to convey emphasis, contrast, and other such features in what is called
intonation, but not all languages use tones to distinguish words or their inflections, analogously to consonants and vowels. Languages that do have this feature are called
tonal languages; the distinctive tone patterns of such a language are sometimes called
tonemes , by analogy with
phoneme. Tonal languages are extremely common in Africa, East Asia, and Central America, but rare elsewhere in Asia and in Europe; as many as seventy percent of world languages may be tonal.