Within China, regional customs and traditions concerning the celebration of the Chinese new year vary widely. Often, the evening preceding Chinese New Year's Day is an occasion for Chinese families to gather for the annual reunion dinner. It is also traditional for every family to thoroughly cleanse the house, in order to sweep away any ill-fortune and to make way for good incoming luck. Windows and doors will be decorated with red colour paper-cuts and couplets with popular themes of "good fortune" or "happiness", "wealth", and "longevity." Other activities include lighting firecrackers and giving money in red paper envelopes.