What algorithm does Chatgpt use?

I'm curious to know, what algorithm does Chatgpt utilize to generate its responses? As an AI language model, I'm sure it relies on some sophisticated method to analyze and produce coherent, meaningful text. Is it based on a traditional transformer architecture like BERT or GPT? Or does it employ a more advanced, specialized approach tailored specifically for conversational applications? I'm eager to gain a deeper understanding of the technical underpinnings of this fascinating technology.