Explained: How ChatGPT and other AI chatbots actually work

ChatGPT is an AI chatbot made by OpenAI, a U.S. company. When it launched in November 2022, it became one of the fastest-growing consumer apps ever, and it set off a race among tech companies to build rival chatbots and AI tools. At its heart is a large language model, or LLM. This is an AI system trained on an enormous amount of text, from books and articles to websites and computer code. During training, the model is repeatedly shown text with the next word hidden and asked to predict it. Over billions of examples, it adjusts a vast number of internal settings until it becomes very good at predicting what comes next. Along the way, it picks up grammar, facts, writing styles and patterns of reasoning.