Chatbot

An automatic responder to text-based queries, usually in the form of a chat room or an instant message format online.

That is, a chatbot is a kind of robot (without a body) who answers your chat. You might type "so...what are you wearing?" The chatbot recognizes the phrase and, based on whatever information it already knows about you, it might say "my FBI badge is still on" or it might say "Um...tee-hee...nothing."

As the missive runs, "On the Internet, nobody knows you're a dog."