Each trade in Vietnam has one founding person called Tổ nghề or Tiên Sư. They are revered for their contribution in creating and teaching the trades to the community.
On January 9 (lunar month), people hold ceremonies to honour their predecessors who have passed the trade on, as well as wish for a good business year.
The honouring tray usually has roasted pork, along with chicken, sticky rice, fruits, etc. In some places, the ceremony is held on January 11 (lunar month) instead.
*Photo: from the Internet