Cantonese is the native language of some 90% of the population of Hong Kong. Although widely considered a dialect of Chinese, Cantonese is not mutually intelligible with Mandarin. It differs substantially from other forms of Chinese in grammar, as well as phonology and lexicon. There are six tones in Hong Kong Cantonese. The romanization used is the JyutPing system developed by the Linguistic Society of Hong Kong. IPA and Yale romanization equivalents are given in Matthews and Yip (1994:400-401).