In Nutshell, answer is dhanteras.it is marks the kickstart of the five-day long Diwali festivities which will be followed by Chhoti Diwali, Diwali, Govardhan Puja and Bhai Dooj.
For easy understand, I attached 5-day Calendar image for 2023 Celebration above.
History and Significance of Dhanteras:
Dhanteras is also called Dhanatrayodashi, marks the start of Diwali celebrations. as per Indian calendar (Saka), It falls on lunar day (Trayodashi Tithi) of Krishna Paksha. Tradition is people buy utensils, jewellery, vehicles, and home/kitchen appliances etc. as there is faith that the festival of Dhanteras is auspicious for buying metals or some home appliances. Devotees also worship Goddess Lakshmi (goddess of wealth) on Dhanteras for happiness, prosperity, and wealth.
1.History of Dhanteras:
Like other religious festivals, Dhanteras is also associated with a mythological anecdote. mass number of people dedicate it to Lord Dhanvantri which is medicine lord, some of the people believe worshipping Lord Yamara and Goddess Lakshmi. so, there are total three major custom related to Dhanteras. among them, two are related with Samudra Manthan, 3rd one is associated with Lord Yamara.
v Story of Lord Dhanvantri:
As per age-old Hindu texts, Dhanvantri is a god of Ayurveda and Medicine. It’s believed that he was the one who imparted knowledge of Ayurveda to mankind and helped them to get rid of diseases. so, on that day devotees pray to Lord Dhanvantri for curing chronic illnesses and keep healthy.
other believed that Lord Dhanvantri was a physician to all the Hindu gods. Ancient Hindu mythological books claim that Dhanvantri was a manifestation of Lord Vishnu & born via Samudra Manthan.
v Story of Goddess Lakshmi:
Another powerfull story on Dhanteras is associated with wealth Goddess Lakshmi. as per Hindu mythology, Goddess Lakshmi appeared through Samudra Manthan was sitting on a lotus with a vessel stocked with gold which symbolize good prosperity, happiness, and wealth.
Tradition is, Devotees make beautiful rangolis, goddess lakshmi sticker at their respective main door and light up their homes with diyas to welcome Goddess Lakshmi and seek her blessings.
Besides, daughters are considered to as Goddess Lakshmi in Hindu families. Rituals of Dhanteras and Lakshmi Pooja also express the belief when daughters or daughters-in-law leave behind their foot impressions at the entrance of their house using ‘kumkum,’ the family is blessed with wealthy and prosperity.
v Story of Lord Yamaraj:
the third and most interesting story is based on King Hima’s son, whose horoscope was predicted that he will die on the 4th day after his marriage because of a snake bite. Upon hearing this, his wife made a plan to turn her husband’s destiny around. She also ensured that her husband didn’t sleep on that day of their marriage by narrating stories and keeping him getup.
To mislead the snake, she made a pile of all her coins and ornaments at their sleeping chamber’s entrance and lit several diyas. When the god of death name Yamaraj arrived incognito mode as a snake, he couldn’t see anything due to the brightness of the diyas and the metals. It is believed that Lord Yamaraj waited there whole night and in early morning he left without killing her husband.so, Dhanteras is also known as Yamadepdaan, where people offer earthen diyas to Lord Yamaraj to please him and pray for the long lives of their family.
2. Significance of Dhanteras:
On the evening of Dhanteras, devotees seek the blessings of Lord Dhanvantri and Goddess Lakshmi to bring peace and happiness to their homes. it’s believed that Goddess Lakshmi only enters a neat and clean house. Hence, on Dhanteras, people clean their houses to attract and invite Goddess Lakshmi into their abode. They light diyas, make rangolis, and put it at the entrance door. People consider Dhanteras extremely auspicious for purchasing gold, silverware, or anything related to metal. They believe it brings good luck and wealth to them.
Dhanteras not only just a festival. It is a collection of mythology, hope, worship, and festivity. People in India dress up in traditional Indian wear and celebrate the festival with utmost zeal and pomp.
hope you have a blessed, healthy and prosperous Diwali.