Not in the modern sense. ELIZA followed hand-written decomposition and reassembly rules. Today's chatbots run on large language models fine-tuned for dialogue, such as Llama 2-Chat.

Chatbot

In short

A chatbot is a computer program you talk to in ordinary language, by typing or speaking, and which replies in kind. Modern AI chatbots such as ChatGPT run on large language models; older ones followed fixed scripts.

Also called: Chat bot, AI chatbot, Conversational AI
Topic: The basics
Level: Beginner
First described: Joseph Weizenbaum's ELIZA, described in Communications of the ACM in 1966, is one of the earliest conversational programs¹.

One of the earliest chatbots was ELIZA, written by Joseph Weizenbaum at MIT and published in 1966¹. It spotted key words in what users typed and used rules to reassemble a reply¹. A 2023 Google DeepMind paper notes that the Turing test often highlights "the ease of fooling people" rather than a machine's intelligence².

The modern wave began when OpenAI released ChatGPT on 30 November 2022. OpenAI said the dialogue format let it "answer followup questions, admit its mistakes, challenge incorrect premises, and reject inappropriate requests"³. Behind such chatbots sits a large language model fine-tuned for conversation, as with Meta's Llama 2-Chat⁴.

Chatbots now front public services. GOV.UK Chat launched in the GOV.UK app in May 2026, letting people ask questions in everyday language instead of searching 80,000 pages of guidance⁵.

A chatbot is not a search engine or an expert. It produces likely-sounding text, and the US standards body NIST lists confabulation, "confidently stated but erroneous or false content", among the main risks of generative AI⁶. NIST also cites studies finding that users may disclose mental health issues to chatbots and react badly to unhelpful responses when in distress⁶.

Example

Asking GOV.UK Chat in the government's app a question in plain English, and getting a conversational answer grounded in official information, is using a chatbot⁵.

Why it matters

Chatbots are how most people meet AI, so knowing they predict text rather than look facts up helps you judge their answers.

Questions people ask

What was the first chatbot?

ELIZA, written by Joseph Weizenbaum at MIT and published in 1966, is one of the earliest and best-known. It matched key words in the user's text and reassembled scripted replies¹.

Is every chatbot AI?

Not in the modern sense. ELIZA followed hand-written decomposition and reassembly rules¹. Today's chatbots run on large language models fine-tuned for dialogue, such as Llama 2-Chat⁴.

Can chatbots be wrong?

Yes. NIST lists confabulation, confidently stated but false content, as a key risk of generative AI⁶. Check important answers against an official source.

Related terms

Tools that use it

Sources

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