Customs

non-exhaustive list, might later be split into multiple articles

Last names: In marriage, often all partners take the last name that carries more status or both partners keep their last name (the latter is most usual in political marriages where debating the importance of both names might start a war^^)
Calendar: Lunar months (28 days long), a week has seven days. The new year starts with the winter solstice. The first month of the year starts on the first new moon of the year