ChatGPT is an AI chatbot powered by the Generative Pre-trained Transformer (GPT) language model. It is a significant step towards artificial general intelligence (AGI) and a more sophisticated type of narrow artificial intelligence (ANI). This article explores the history of ChatGPT, from its inception in 2018 with GPT-1 to the more recent GPT-2. GPT-1 was revolutionary as it was capable of producing coherent sentences and paragraphs that were nearly identical to those written by humans. GPT-2 was an improved version of GPT-1, with more parameters and better performance.