# What is an LLM (and an answer engine)?

**Category:** Concept

## TL;DR

An LLM (large language model) is the AI behind tools like ChatGPT, Claude, and Gemini — trained on huge amounts of text to understand and generate language. An answer engine is a product (ChatGPT, Perplexity, Google's AI Overviews) that uses an LLM to answer a question directly, often citing the sources it drew from.

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## What it is

An LLM is like an extraordinarily well-read assistant: it has read an enormous slice of the internet and predicts, word by word, the most helpful response to what you ask. It doesn't "look things up" the way a database does — it draws on patterns learned in training, and increasingly on live content it retrieves at question time.

An **answer engine** wraps that ability in a search-like experience: instead of ten blue links, you get a written answer — and, more and more, a short list of the sources behind it. That "cited sources" part is where your website comes in.

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## Why it matters

- **They read the web through machines.** LLMs and their crawlers parse pages far better when the facts are labeled — via structured data and files like `llms.txt` — than when they're buried in messy HTML.
- **Citations are the new clicks.** Being the source an answer engine quotes is the AI-era equivalent of ranking on page one.
- **Access is a choice.** `robots.txt` lets you decide which AI crawlers may read you at all.

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## How MetaPilot handles it

MetaPilot makes your pages easy for LLMs to parse — accurate structured data, a fresh `llms.txt`, and clean edge delivery — and shows you which AI crawlers are actually visiting, so you can see and shape how answer engines read your site.

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## FAQ

**Do LLMs actually read my website?**
Their crawlers can (GPTBot, ClaudeBot, PerplexityBot, and others), and answer engines retrieve live pages to cite. You can allow or block them in `robots.txt`.

**How do I get cited by an answer engine?**
Make your content easy to parse and trust: clear structure, accurate structured data, freshness, and access for the crawlers you want. That's the heart of AEO (Answer Engine Optimization).

**Is training the same as being cited?**
No — training uses content to build the model; citation happens when an engine retrieves and references your page in an answer. You can feel differently about each, and control crawlers accordingly.

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## Related

- What is Answer Engine Optimization (AEO)?
- What are llms.txt and llms-full.txt?
- What is structured data?
- What is robots.txt?