ChatGPT

Founded in December 2015 in San Francisco by Sam Altman, Elon Musk, Greg Brockman, Ilya Sutskever and others, OpenAI set itself the initial mission of developing beneficial artificial general intelligence. The organisation, at first a non-profit, shifted in 2019 to a "capped profit" structure allowing capital to be raised; Microsoft invested one billion dollars in July 2019 and a further ten billion in January 2023. OpenAI successively released the models GPT-1 (2018), GPT-2 (February 2019) and GPT-3 (June 2020), all based on the transformer architecture introduced in 2017 by Google researchers in the paper "Attention Is All You Need". Training on hundreds of billions of words from the Web, books and Wikipedia produced language models with impressive capabilities, but still difficult to use outside a research context. ChatGPT was launched on 30 November 2022 as a simple research prototype intended to gather user feedback. It relied on the GPT-3.5 model, a refined version of GPT-3, fine-tuned through supervised learning and reinforcement learning from human feedback (RLHF), a method described in the 2022 InstructGPT papers. The deliberately austere interface — a plain dialogue box — hid a model of several hundred billion parameters. The product met with unprecedented adoption: one million users in five days, one hundred million in two months, making it the fastest-growing consumer application in history. Subsequent versions integrated GPT-4 (March 2023), vision, voice and agent capabilities that can browse the Web. The success of ChatGPT shook the whole industry. Google reacted with Bard and then Gemini, Anthropic released Claude, Meta open-sourced the Llama series, Mistral emerged in Europe. Hundreds of millions of monthly users now rely on conversational assistants to write, program, translate, teach or summarise. The economic, legal, educational and political implications — copyright, hallucinations, disinformation, employment — have become central to public debate. ChatGPT marks the general public's effective entry into the generative AI era and consolidates the founding role of Sam Altman in this historical sequence.