Nine avatars of Maa Durga are worshipped during Navratri festival which begins on October 3. The nine avatars are - Maa Shailputri, Maa Brahmacharini, Maa Chandraghanta, Maa Kushmanda, Maa Skandamata, Maa Katyayani, Maa Kalaratri, Maa Mahagauri and Maa Siddhidatri. These nine forms of Adi Shakti are known as Navadurga. Navratri marks Goddess Durga's victory over the evil Mahishasura.