Karva Chauth is a festival celebrated by Hindu women of Northern and Western India on the fourth day after Purnima (a full moon) in the month of Ashwin. Like many Hindu festivals, Karva Chauth is based on the lunisolar calendar which accounts for all astronomical positions, especially positions of the moon which is used as a marker to calculate important dates. The festival falls on the fourth day after the full moon. On Karva Chauth, married women and unmarried women, especially observe fast from sunrise to moonrise for the safety and longevity of their husbands. The Karva Chauth fast is traditionally celebrated in the states of Delhi, Haryana, Rajasthan, Punjab, Jammu,Madhya Pradesh,Uttar Pradesh, Himachal Pradesh. It is celebrated as Atla Tadde in Andhra Pradesh. Origins Karva is another word for 'pot' (a small earthen pot of water) and chauth means 'fourth' in Hindi (a reference to the fact that the festival falls on the fourth day of the dark-fortnight, or Krishna paksh, of the month of Kartik). In Sanskrit scriptures, the festival is addressed as Karka Chaturthi, Karka meaning an earthen water pitcher and Chaturthi denotes fourth day of lunar Hindu month. Karva Chauth is mostly celebrated in Northern India. One hypothesis is that military campaigns were often conducted by men in far off places whereby men would leave their wives and children at home to go off to the war. Their wives would often pray for their safe return. The festival also coincides with the wheat-sowing time (i.e., the beginning of the Rabi crop cycle). Big earthen pots in which wheat is stored are sometimes called Karvas, so the fast may have begun as a prayer for a good harvest in this predominantly wheat-eating Northwestern region. Another story about the origin of this festival relates to the bond of feminine friendship. With the custom of arranged marriage being prevalent, the newlywed is supposed to reside with her husband and in-laws. Being new to the family, the custom arose of befriending another woman as her friend (kangan-saheli) or sister (dharam-behn) for life. The friendship would be sanctified through a Hindu ritual during the marriage ceremony itself. The bride's friend would usually be of the same age (or slightly older), typically married into the same village (so that she would not go away) and not directly related to her in-laws (so there was no conflict of interest later). This emotional and