Tet is celebrated from the first day of the first month of the Lunar calendar (around late January and early February) until at least the third day. It is the first and foremost part of Vietnam’s traditional festival systems which holds the plentiful and profound contents in terms of ritual and festival. There are lots of customs practiced during Tet, such as visiting a person’s house on the first day of the new year, ancestral worshipping, wishing New Year’s greetings, giving lucky money to children and elderly people, and opening a shop.