ELIZA is one of the first chat bots, created between 1964 and 1966 by Joseph Weizenbaum as a parody of responses of a psychotherapist in an initial psychiatric interview. Weizenbaum meant to demonstrate the superficiality of communication between humans and machines and was surprised when people started attributing human-like feelings to it.

I had not realized … that extremely short exposures to a relatively simple computer program could induce powerful delusional thinking in quite normal people.

You can learn more about ELIZA on its Wikipedia page. (Image via Wikipedia.)