Chatbots: A long and complicated history

In the 1960s, an unprecedented computer program called Eliza attempted to simulate the experience of speaking to a therapist. In one exchange, captured in a research paper at the time, a person revealed that her boyfriend had described her as "depressed much of the time." Eliza's response: "I am sorry to hear you are depressed." Eliza, which is widely characterized as the first chatbot, wasn't as versatile as similar services today. The program, which relied on natural language understanding, reacted to key words and then essentially punted the dialogue back to the user.