ChatGPT (Chat Generative Pre-Trained Transformer) is an artificial intelligence chatbot developed by OpenAI and launched on November 30, 2022. It is notable for enabling users to refine and steer a conversation towards a desired length, format, style, level of detail, and language used. Successive prompts and replies are taken into account at each stage of the conversation as a context.^[2]

ChatGPT is built upon GPT-3.5 and GPT-4, from OpenAI's proprietary series of foundational GPT models. These large language models (LLMs)^[3] have been fine-tuned for conversational applications using a combination of supervised and reinforcement learning techniques. According to LLM experts, this training has made ChatGPT better at handling "hallucinations" than its preceding model, GPT-3, but ChatGPT is still known to confidently present inaccurate information.^[4][5] ChatGPT was released as a freely available research preview, but due to its popularity, OpenAI now operates the service on a freemium model. It allows users on its free tier to access the GPT-3.5 based version, while the more advanced GPT-4 based version, as well as priority access to newer features, are provided to paid subscribers under the commercial name "ChatGPT Plus".

By January 2023, it had become the fastest-growing consumer software application in history, gaining over 100 million users and contributing to OpenAI's valuation growing to US$29 billion.^[6][7] Within months, Google, Baidu, and Meta accelerated the development of their competing products: Bard, Ernie Bot, and LLaMA.^[8] Some observers expressed concern over the potential of ChatGPT to displace or atrophy human intelligence, and its potential to enable plagiarism or fuel misinformation.^[9]