The Sharad Purnima or Kojaagari Purnima is a harvest festival celebrated on the full moon day of the Hindu lunar month of Ashwin (September-October). The rainy season is over and the brightness of the full moon brings special joy. This is a traditional celebration of the moon and is also called the Kaumudi celebration, Kaumudi meaning moonlight.
At night, goddess Laxmi is worshipped and night vigil is observed. According to a folk-tale, once a king fell on evil days, and was in great financial straits, but then his queen observed this fast and night vigil, and worshipped the goddess of wealth, Laxmi. Consequently, they were blessed by the goddess and they regained their prosperity.
Some people believe that on this night Laxmi moves about from place to place asking, "Who is awake?" ("Kojagarti?") and shows her pleasure on those she finds awake. Hence, the night is spent in festivity and various games of amusement, in honour of the goddess. So people sit in the moonlight singing songs, or keep themselves entertained in some other way. They fast from solid food and take only fluids like coconut water or milk. Milk is boiled until it thickens, and milk masala (called kheer, a readymade combination of dry fruits) is added to it and drunk. There is also the tradition to have cool Milk & Rice flakes on this night. It is a harvest festival and is celebrated throughout the country, particularly by Maharashtrians i.e. by people residing in Maharashtra, India. The eldest child of the family is also honoured on this day.