Quick answer: A chatbot works by taking your message, working out what you mean, and generating or choosing a reply. Simple rule-based chatbots match keywords to pre-written answers. Modern AI chatbots such as ChatGPT, Claude and Gemini use large language models (LLMs) trained on huge amounts of text to predict a helpful response word by word, often combined with company documents or live search so the answer is accurate and up to date.
The two main types of chatbot
| Rule-based chatbot | AI (LLM) chatbot | |
|---|---|---|
| How it answers | Follows set rules, buttons and decision trees | Generates new replies from a language model |
| Understands | Exact keywords or menu choices | Natural language, typos and follow-up questions |
| Best for | Simple FAQs, booking, order tracking | Open questions, writing, research, support |
| Risks | Gets stuck outside its script | Can sound confident but be wrong (“hallucinations”) |
| Cost to set up | Low | Higher, but much more capable |
How an AI chatbot works, step by step
- You send a message. The text (or your voice, converted to text) is sent to the chatbot.
- Tokenisation. The message is broken into small pieces called tokens, roughly parts of words.
- Understanding context. The model looks at your message together with the earlier conversation and any instructions set by the company running the chatbot.
- Retrieval (optional). Many business chatbots search a knowledge base, website or product database and add the relevant facts to the prompt. This is called retrieval-augmented generation (RAG) and helps keep answers accurate.
- Generating the reply. The language model predicts the most useful next token again and again until it forms a full answer.
- Safety and formatting. Filters check the reply against rules, and it is formatted for the chat window.
- Actions (optional). Advanced chatbots, often called AI agents, can also take actions such as booking an appointment, checking an order or updating a CRM through connected tools.
Key technologies behind chatbots
- Natural language processing (NLP): the field of AI that helps computers understand and produce human language.
- Large language models (LLMs): neural networks trained on vast text collections to understand and generate language.
- Intent detection: working out what the user wants, for example “track my order” or “cancel subscription”.
- Entity extraction: picking out details such as dates, names, order numbers or locations.
- Machine learning feedback: improving answers based on ratings and conversation reviews.
How businesses use chatbots
- Customer support: answering common questions 24/7 and passing complex issues to a human.
- Lead generation: qualifying website visitors and booking calls.
- Ecommerce: product recommendations, order tracking and returns.
- Internal help desks: HR and IT questions for staff.
- Marketing: chat on Facebook Messenger, Instagram and WhatsApp. See AI in digital marketing trends.
How to add a chatbot to your website
- Decide the job: FAQs, lead capture, bookings or support.
- Choose a tool: many live chat and CRM platforms include AI chatbots that learn from your website and help articles.
- Give it good source material: clear FAQs, policies, prices and product information.
- Set limits: what it should not answer, and when to hand over to a person.
- Test with real questions, then review conversations weekly and improve.
Limitations to know about
- AI chatbots can make mistakes, so check important facts and keep a human route available.
- They only know what they were trained on or can access, so out-of-date sources give out-of-date answers.
- Do not share sensitive personal or financial details with public chatbots. Businesses must follow UK GDPR when chatbots handle customer data.
Frequently asked questions
Is a chatbot the same as AI?
Not always. Rule-based chatbots follow scripts and use no AI. Modern chatbots like ChatGPT, Claude and Gemini are powered by AI language models.
How do chatbots learn?
AI chatbots learn language during training on large text datasets. Business chatbots are then given company information so they can answer specific questions, and are improved using feedback.
Do chatbots remember conversations?
Within a single chat they use the earlier messages as context. Some assistants also offer optional memory features or saved chat history. See how to archive and manage chatbot conversations.
Can a chatbot replace customer service staff?
It can handle many routine questions, but people are still needed for complex, sensitive or high-value conversations.