Natural Language Understanding NLU is the secret of how Voicebot could understand human language. NLU is not only finding the keywords in the sentence, but finding the entity and intention, and then search for the answer that matches the most. So, A.I. cannot really ‘think’ like a human although it seems to be able to understand human language. It reminds me of a test, which is about identifying if an object can think, done by Turing in 1950. Since we could not identify what is ‘Artificial Intelligence’, if a machine can have a conversation with human, and the human could not identify it is a machine or not, then the machine will be defined as having intelligence.