Terminology
In formal Cantonese, the 圓 character is used. In spoken Cantonese, 蚊 is used, perhaps a transliteration of the first syllable of "money", although some suggest that the character is a corruption of 緡. 元 is also used informally. The dollar is divided into 100 cents, with the character 仙 (a transliteration of "cent") used on coins and in spoken Cantonese. However, 仙 is now only used in the stock market, as now it no longer has a note or coin form due to its small value, and is no longer used in regular transactions. 分 is used in Mandarin. The amount of 10 cents is called 1 houh in Cantonese (毫 on coins and in spoken Cantonese, 毫子 in colloquial speech, 角 in Mandarin). The mil was known as the man or tsin in Cantonese (萬 or 千 on coins and in spoken Cantonese and Mandarin).
To express prices in spoken Cantonese, for example $7.80, the phrase is 七個八 (chat go baat, seven units and eight ); in financial terms, where integer values in cents exist, e.g., $6.75, the phrase is 六個七毫半 (luhk go chat houh bun, six and seven "houh" half) (fives in cents is normally expressed as "half", unless followed by another five, such as 55 cents when preceded by a dollar value); $7.08 is 七蚊零八仙 (seven dollars "ling" (zero) eight cents).
Read more about this topic: Hong Kong Dollar