Diwali, an important and auspicious festival of hindus is celebrated for five long days with great pomp and show in India. People buy new things and decorate their houses with lights and diyas. The five days celebrated are Dhanteras, Narak Chaturdasi, Diwali, Goverdhan and Bhai dooj.
The first day of this long festival is celebrated as Dhanteras. Dhanteras also called Dhanatrayodashi or Dhanvantari Trayodashi. It is called Dhanteras because it is celebrated on the thirteenth lunar day of Krishna Paksha (dark fortnight) in the Vikram Samvat Hindu calendar month of Karthik. Dhanteras is marked auspicious for buying any new thing in house especially gold,silver and kitchenware. It is believed that buying new metal or Dhan will bring good luck. Many stories are behind celebrating this pious day. The god of Ayurveda, lord Dhanvantri who gave the theory of ayurveda to get people rid out of diseases is also worshiped on this day. Second, on the day of Dhanteras, Goddess Lakshmi came out from the ocean of milk during the churning of the Sea. Hence, Goddess Lakshmi is worshiped on the day of teras.

People thoroughly clean their houses to worship goddess of wealth, Lakshmi in the evening. Entrances were decorated with bandanwars, rangoli and beautiful diyas. In honor of Lakshmi and Dhanvantari, diyas are kept burning for whole night.
The day after Dhanteras is celebrated as Narak chaturdasi or choti Diwali. People light diyas for whole night glorifying Yama, the god of death.