ChatGPT is a large language model developed by OpenAI. It was trained on a dataset of billions of words, with the goal of being able to generate human-like text and answer questions on a wide range of topics. ChatGPT is able to browse the internet and therefore access new information beyond what it was trained on. It is able to process and respond to text input, but may not always provide accurate or complete answers, especially on topics that are outside of its training data.
With a subscription however, it is also able to use plugins and which vary from booking flights, over video summarization to build your own personal trainer.