As it is believed that snakes have more powers than humans and on account of its association with Shiva, Devi, Vishnu and Subramanya, a degree of fear is instilled resulting in deification of the cobra and its worship throughout the country by Hindus.

Snake has connotation with the Moon’s nodes known in Hindu astrology.
The head of the snake is represented by Rahu ("Dragon's head") and its tail by Ketu ("Dragon's tail").
If in the zodiacal chart of an individual all the seven major planets are hemmed between Rahu and Ketu in the reverse order (anticlockwise) it is said to denote Kalasarpa dosha (Defect due to black snakes), which forebodes ill luck and hardship in an individual's life and therefore appeased by offering worship to the snakes on Naga Panchami day.
As it is believed that snakes have more powers than humans and on account of its association with Shiva, Devi, Vishnu and Subramanya, a degree of fear is instilled resulting in deification of the cobra and its worship throughout the country by Hindus.
Snake has connotation with the Moon’s nodes known in Hindu astrology. The head of the snake is represented by Rahu ("Dragon's head") and its tail by Ketu ("Dragon's tail"). If in the zodiacal chart of an individual all the seven major planets are hemmed between Rahu and Ketu in the reverse order (anticlockwise) it is said to denote Kalasarpa dosha (Defect due to black snakes), which forebodes ill luck and hardship in an individual's life and therefore appeased by offering worship to the snakes on Naga Panchami day.
Naga Panchami