Machine Learning (ML): This is the basic form of AI in which computers learn from data to perform certain tasks, such as recognising images or predicting trends. ML models get better as they get more data. 

Large Language Models (LLMs): this particular form of machine learning is trained on huge amounts of text. The models understand and generate text that appears to be written by humans, such as stories or answers to questions. ChatGPT is an example that uses a LLM as underlying technology. 

Generative AI: this branch of AI not only analyses, but also creates new content such as images, music or sound. LLMs like ChatGPT also fall under this, but generative AI can produce much more than just language; for example, it can also create new artworks or videos.