ChatGPT is a generative artificial intelligence chatbot developed by OpenAI and released on November 30, 2022. It uses large language models (LLMs) such as GPT-4o as well as other multimodal models to create human-like responses in text, speech, and images. It has access to features such as searching the web, using apps, and running programs. It is credited with accelerating the AI boom, an ongoing period of rapid investment in and public attention to the field of artificial intelligence (AI). Some observers have raised concern about the potential of ChatGPT and similar programs to displace human intelligence, enable plagiarism, or fuel misinformation. ChatGPT is built on OpenAI's proprietary series of generative pre-trained transformer (GPT) models and is fine-tuned for conversational applications using a combination of supervised learning and reinforcement learning from human feedback. Successive user prompts and replies are considered as context at each stage of the conversation. ChatGPT was released as a freely available research preview, but due to its popularity, OpenAI now operates the service on a freemium model. Users on its free tier can access GPT-4o but at a reduced limit. The ChatGPT subscriptions "Plus", "Pro", "Team", and "Enterprise" provide increased usage limits and access to additional features or models. Users on the Pro plan have unlimited usage, except for abuse guardrails. By January 2023, ChatGPT had become the fastest-growing consumer software application in history, gaining over 100 million users in two months. ChatGPT's release spurred the release of competing products, including Gemini, Claude, Llama, Ernie, and Grok. Microsoft launched Copilot, initially based on OpenAI's GPT-4. In May 2024, a partnership between Apple Inc. and OpenAI was announced, in which ChatGPT was integrated into the Apple Intelligence feature of Apple operating systems. As of May 2025, ChatGPT's website is among the 5 most-visited websites globally. Source: Wikipedia (en)