ChatGPT was created by OpenAI, an artificial intelligence research company founded in 2015. OpenAI initially started as a nonprofit but transitioned to a for-profit model in 2019. The company is led by CEO Sam Altman, who is also a co-founder. OpenAI developed ChatGPT based on its series of generative pre- trained transformer (GPT) models, with ChatGPT being fine-tuned for conversational use. The first public release of ChatGPT was in November 2022 as a free research preview, and it quickly became one of the fastest-growing consumer software applications in history

. Key figures involved in OpenAI's founding include Sam Altman and Elon Musk, among others, though Musk is no longer directly involved. The development of ChatGPT built on earlier GPT models, evolving from GPT-1 through GPT-4, with ChatGPT-4 being the latest advanced conversational AI version

. In summary, ChatGPT was made by OpenAI, a company dedicated to advancing AI technology for broad benefit, with leadership from Sam Altman and a team of researchers and engineers