An AI program you talk to through messages.
A chatbot is your group-chat friend with no bedtime. Text it at 3 a.m. It replies before your pizza rolls get hot.
You meet it in customer support, small talk, and quick Q&A. It is often the front desk of an AI product.
ELIZA
ELIZA was a classic early chatbot.
LLM
Modern chatbots often use an LLM to understand and write replies.
ChatGPT
ChatGPT brought chatbots to everyday people.
Agent
An Agent can plan and do tasks beyond chatting.