Durga is Adi-Parashakti herself. The Devi Gita, declares her to be the greatest Goddess. Thus, she is considered the supreme goddess and primary deity in Shaktism, occupying a place similar to Lord Krishna in Vaishnavism. According to Skanda Purana, the goddess Parvati accounted the name "Durga" after she killed the demon Mahishasura.
The trishul or trident she holds is symbolic of the three human qualities Satwa (Inactivity or the ideal state of mind characterized by awareness and purity of thought), Rajas (activity or energy associated with desires, wishes and ambitions) and Tamas (lethargy and stress). In order to attain peace and happiness, there needs to be the balance between these three qualities.
Durga Puja commemorates Prince Rama’s offering to Maa Durga before going to war with the demon king Ravana. Lord Rama first worshiped the ‘Mahishasura Mardini’ (the other name for the Goddess) or the assassin of the buffalo-demon, by offering 108 blue lotuses and lighting 108 lamps.
