In some countries, such as Vietnam, everyone celebrates their birthday on the same day - New Year's Day! As well as birthdays, you might also get an invitation to a party to celebrate moving to a new home - a housewarming party - in the U.S.A., India, and other countries. In some places,people have farewell parties to say goodbye to someone who is leaving a job, school, or a neighborhood.And in some countries, parties celebrate national holidays, like Independence Day in Mexico.