Vietnamese uses both two kinds of calendar, one is Solar Calendar and other is the Lunar Calendar.  The Solar Calendar is marked for the business year and much more of other things and for people who lives in the cities. While people in the countryside, they put their heart on the Tet and still keep a lots of custom as that is Vietnamese traditional New Year.  "Tet" is a word of Chinese Origin. It is the phonetic deformation of "Tiet", a SinoVietnamese term which means "Joint of a bamboo stern" and in a wider sense, the "beginning of a period of the year". The passage from one period to the next may cause a meteorological disturbance (heat, rain, mist) that must be exercised by ritual sacrifices and festivities. Thus, there are many Tets throughout the year (Mid-autumn Vietnamese New Year, Cold Food Vietnamese New Year, etc.). The most significant of all is "Vietnamese New Year Ca" ("Big Vietnamese New Year" or simply "Vietnamese New Year"), which marks the Lunar New Year.

Vietnamese New Year occurs somewhere in the last ten days of January or the first twenty days of February, nearly halfway between winter solstice and spring equinox. Although the Lunar New Year is observed throughout East Asia, each country celebrates Vietnamese New Year in its own way in conformity with its own national psyche and cultural conditions.  For the Vietnamese people, Vietnamese New Year is like a combination of Western Saint Sylvester, New Year's Day, Christmas, Easter and Thanksgiving. It is the festival of Purity and Renewal. ( source: vietnam-culture.com )

Before TET:
Before the New Year, people are very busy for clean up everything in their house. Washing all the clothes, blankets, mosquito nets, curtains…. They will go to the market to buy the new clothes and a lot of foods. Vietnamese people believe that they will have a very prosperous year if they have enough food and water for some first days of the New Year.
On Tet season, there are many kinds of flowers blossom at the same time as that is a spring season also. There are two special feature flowers those are “ Mai” in the South and “ Dao “ in the North.

Flowers also “ blossoming” in a street. There are many “ flower streets” on every district/town where they display many kinds of flower around 7 -10 days before Tet.  - On the 23th of December of Lunar Year, people will buy flowers and some kind of biscuits or candies to pray to the “ Ong Tao”. According to Vietnamese legend, “ Ong Tao” is called for the fire-cook,” he” will go to report to God about all of the good and bad thing which people have doing during year.  - On the 30th or the last day of the old Lunar year, people will pray to bring him back to their house and the “ Ong Tao” will stay with them for another year.  - On the last day of the old Lunar Year, Vietnamese people will set up a special meal to pray and ask their ancestors to come home for having Tet with them. Since that day, people will pray to their ancestor everyday in the morning with hot tea and some sweet things. Some families they offer food as meat, chicken… that depend on their affordable life. When it is more developed, Vietnam railway network is possibly linked to Cambodia, Thailand and Malaysia railways network via which to Singapore and Laos railways.

Tet festival		Dao Flower		Banh Chung		Banh Tet

On that last day, most of the families already got rice, meat, chicken , flowers, fruits, “ banh chung” in the North and “ banh tet” in the South and many other kinds of foods.
They are ready to celebrate the Tet as they will spend at least 1 week for enjoying after a year working.

During Tet:

Vietnamese people believe that the first person who comes to their house will decide the lucky or unlucky for their family in the whole year. So people often stay home on the first day and will go for greetings others on the second day and on. On the first 3 days, they are not sweep their house or just sweep from the door into the house as the money will not go out but come in for the whole year. For the first day, children will get the lucky money from their parents and their relatives or their visitors. The amount is depend on each person but meaning of the luckily.