As per the Hindu calendar, Diwali is observed on Amavasya (or new moon) - the 15th day - of the month of Kartik, every year. On this day, Goddess Lakshmi and Lord Ganesha are worshipped in the worship known as Deepavali Puja or Lakshmi Ganesh Pujan. This year it falls on Octover 23 all over the country.