In Greek mythology, Narcissus is a beautiful young man who falls in love with his own reflection in a pool of water: 

Story

Narcissus is the son of the nymph Liriope and the river god Cephissus. A prophet told Liriope that Narcissus would live a long life if he never recognized himself. Narcissus was cruel to those who sought his affection, and rejected the love of the nymph Echo. While hunting, Narcissus bent down to drink from a spring and fell in love with his own reflection. He pined away and died, and the flower that bears his name grew where he died. 

Symbolism

Narcissus's story is a tale of unrequited love and self-obsession. The term "narcissism" comes from the character of Narcissus, and describes a personality style that is self-centered. The term "narcissistic personality disorder" is also based on the myth, and describes a condition characterized by excessive need for attention, grandiosity, and an inability to empathize. 

Influence

The story of Narcissus was popular in Roman art, and was a source of inspiration for Renaissance and later responses to the myth. Sigmund Freud used the myth as a symbol of self-absorption in his psychoanalytical concept of narcissism. 

Variations

There are different versions of the story of Narcissus. For example, in one version, Narcissus's mother was the goddess of the moon, Selene, and his father was Endymion.