Sheshnag is a mythical serpent in Hindu mythology, often depicted with multiple heads, typically five or seven. He is considered a divine being and is associated with the god Vishnu, serving as his bed and protector. Sheshnag is believed to hold the universe on his hoods and is a symbol of eternity and the cycle of creation and destruction. In various texts, Sheshnag is also linked to the cosmic ocean, where he plays a role during the churning of the ocean, known as Samudra Manthan. His presence signifies the balance of nature and the importance of serpents in Hindu culture, representing both danger and protection.