Dhanteras ki Katha and Pooja

It is Dhantrayodashi, the thirteenth day of the waxing moon in the month of Ashwin (September-October) i.e. two days before the Diwali day. People clean their houses and invite Lakshmi (Goddess of wealth) by lighting an earthen lamp at the doorstep of their houses. Once Lord Vishnu and his wife Lakshmi visited the planet earth and stayed under a Peepal tree. 

Lord Vishnu went away on an urgent visit and told her not to look towards the south until he return, Unfortunately, she could not resist looking towards the south as it was full of beautiful flowers and sugarcane-fields. As a punishment for not obeying the Lord, she was asked to work in a farmer's field for twelve years. 

After twelve years Lakshmi wanted to be free and the farmer told her that due to her company his family has become very happy and prosperous and would not like her to leave his house. The farmer saw a dream that goddess Lakshmi was in their house and that is why they were becoming prosperous and rich. 

The goddess was impressed by their devotion towards her and told them that tomorrow is Dhan Teras therefore you clean your house and light the earthen lamp at the door and you can worship me, but I will remain invisible in your house. The farmer did as he was told and became very rich and prosperous. People still believe the story and worship the goddess for happiness and wealth. Some people also keep fast on this day.