Taboos about Numbers

In Chinese culture, certain numbers are believed by some to be auspicious or inauspicious based on the Chinese word that the number name sounds similar to. However some Chinese people regard these beliefs to be superstitions. Since the pronunciation and the vocabulary may be different in different Chinese dialects, the rules are generally not applicable for all cases.
Because of the supposed auspiciousness of certain numbers, some people will often choose, attempt to obtain, or pay large sums for numbers that are considered to be lucky for their phone numbers, street addresses, residence floor (in a multi story building), driver's license number, vehicle license plate number, bank account number, etc.
Lucky numbers are based on Chinese words that sound similar to other Chinese words. The numbers 6, 8, and 9 are believed to have auspicious meanings because their names sound similar to words that have positive meanings.