ChatGPT is a large-scale pre-training language model developed by OpenAI. It is a variant of GPT-3 model, and GPT-3 can generate human-like text responses in dialogue after training. ChatGPT is designed as a chat robot, and we can fine-tune it to complete various tasks, such as answering questions, providing information or participating in conversations. Unlike many chat bots that use predefined responses or rules to generate text, ChatGPT is trained to generate responses according to the input received, thus generating more natural and diverse responses.