According to the Puranic myth, it is said that the origin of Nagas have been directly related to Brahma and that is why they are considered auspicious. It is believed that Brahma’s son Kashyapa had four wives. His first wife is the mother of all Devas, second to Garudas, third to Nagas and fourth to Daityas. The third wife of Kashyapa, who was named Kadroo gave birth to Nagas after whom the Nagas are also known as Kadrooja. They were once the rulers of nether world, the Patal Loka.
The Naga Panchami, which falls on the fifth day of the moonlit-fortnight in the month of Shravan according to the Hindu calendar (July / August according to the Gregorian calendar), is celebrated in order to commemorate the existence of the Nagas. It is said that the prominent Nagas in the Puranas that are to be worshiped are Anant, Vasuki, Shesh, Padma, Kanwal, Karkotak, Kalia, Aswatar, Takshak, Sankhpal, Dhritarashtra and Pingal. Though, some historians claim that these were not snakes but Naga Kings of various kingdoms which were worshiped as Gods.
The association of snakes, gods and human in Indian legends have also promoted the widespread believe of the fact that snakes have an eternal attachment with the Hindu religion. It is evident from the Hindu mythologies that how snakes have been associated with Lord Krishna, Shiva and Vishnu in various stages of their existence. The existence of snakes in the ancient Hindu puranas and texts also prove the long association of Human race and the snakes.
On the day of Nag Panchami in Shravan month, followers of Nagas worship Naga Devata (Cobras) with full devotion. They visit temples and snake pits and offer prayers to the snakes. Milk and silver jewelry is offered to the Cobras in order to please them and seek their protection from all evils. The devotees also observe a full day fast on this day. Swings are put up in the villages and people enjoy themselves while singing shravan songs.