Eliza

ELIZA was an early chatbot created by Joseph Weizenbaum. It used simple template matching together with some fixed prompts which it applied in a semi-random fashion. The most well known variant was based on Rogerian psychology, where the human therapist is trained to reflect back the patient's statements. For example, if ELIZA detected key terms such as 'mother' in the user's input, it might say "tell me more about your mother".