What an LLM is, in plain words
A large language model is the software behind AI chat tools. It writes answers in sentences instead of showing a list of links. When someone asks it for a recommendation, it may name a few businesses, and LLM SEO is about making sure that yours is described accurately when that happens.
LLM SEO, GEO, AEO and SEO: how the names relate
There is no official standard, and writers use the terms differently. A working guide:
| Term | Stands for | What it usually means |
|---|---|---|
| SEO | Search engine optimisation | Ranking pages in a list of search results |
| AEO | Answer engine optimisation | Being the direct answer to a question |
| GEO | Generative engine optimisation | Being named inside an answer an AI writes |
| LLM SEO | Large language model SEO | Mostly the same as GEO, named after the technology |
Many people use GEO, AEO and LLM SEO as near-synonyms. When you read a source, check which meaning it intends. AEO vs GEO vs SEO goes through the differences.
Two ways an LLM learns about your brand
OpenAI separates its crawlers by job, and that shows two routes.
- What the model has already learned. Some web crawling is used to train models. OpenAI lists GPTBot as the crawler that may gather content for training, and says blocking it tells OpenAI the content should not be used for that.
- What it finds when it searches. Tools such as ChatGPT can also search the web for a question and cite what they find. OpenAI lists OAI-SearchBot as the crawler that surfaces sites in ChatGPT's search features.
You can influence the second route more directly, because pages that are clear, current and consistent are what a search can retrieve. The first route changes only when the model is updated, on the provider's schedule.
What to do to optimise a brand for LLMs
- Do the SEO basics. Pages that can be crawled, load quickly and answer real questions are the base. Google says there are no extra requirements to appear in its AI Overviews and AI Mode, and no special schema is needed.
- Answer first and spell terms out. Put the plain answer in the first two sentences. Spell out acronyms such as GEO and AEO the first time. In our test on 7 October 2026, ChatGPT answered about something other than this discipline on six of seven questions that used GEO or AEO. It is one test on one day.
- Keep your facts the same everywhere. Name, description, address, services and prices should match across your site and your profiles.
- Cite your sources and date your pages. Evidence with a date is easier to trust and to check.
- Be mentioned on other credible sites. Reviews, directories and press help an AI tool confirm what you do. Whether a publisher mentions you is the publisher's decision.
- Measure by asking. Ask the questions your buyers ask on the main AI tools on a schedule. Record whether you are named, whether your site is cited and whether the description is right.
What about llms.txt?
llms.txt is a proposed file that summarises a site for language models. Google says you do not need new machine-readable files, AI text files or markup for its AI features. Treat llms.txt as optional housekeeping, and do not expect it to change what an AI tool says. llms.txt and robots.txt for AI crawlers covers it in more detail.
What no one can promise
No one controls what an AI tool names. Engines change how they decide without notice. The honest commitment is to do the work and to measure the result. Request an audit to see what AI tools say about your brand today.