In Greek mythology, Thanatos is a figure who represents death. In psychoanalysis, Thanatos is a person's urge toward death or self-harm.
In the myth of Thanatos, he is described as the son of Nyx (Night) and Erebos (Darkness), and the twin brother of Hypnos (Sleep). Sigmund Freud, the founder of psychoanalysis, adopted the concept of the "death drive," later called Thanatos. In post-Freudian theory, Thanatos is said to balance out Eros, the urge to stay alive and to be creative and productive. The word's origin is Greek, from a root meaning "to disappear."