Durga Puja is celebrated in the Hindu calendar month of Ashvin, which falls in September or October. This is a 10-day festival which, this year, starts on October 22. The first nine days are called “Navratri.” People offer prayers (puja) to Goddess Durga for slaying the buffalo demon Mahishasur. The festival ends on the 10th day. The victory of King Rama, an avatar of Vishnu, who vanquished the 10-headed demon Ravana, is also celebrated. Ravana’s effigy is burned and prayers offered. Durga Puja symbolizes the victory of good over evil.