For example, there are chatbots

A chatbot can be any software/system that holds dialogue with you/a person but doesn’t necessarily have to be AI-powered.

For example, there are chatbots that are rules-based in the sense that they’ll give canned responses to questions.

ChatGPT is AI-powered and utilizes LLM technology to generate text after a prompt.

Can ChatGPT write essays?
Yes.

Can ChatGPT commit libel?
Due to the nature of how these models work, they don’t know or care whether something is true, only that it looks true.