SEO vs GEO vs AEO vs AIO: what the terms mean and what to do

If you have searched for SEO vs GEO vs AEO vs AIO, you have probably seen the same work sold under four names. For a salon in Lillestrøm or a plumber in Oslo, the question is practical: when a customer asks Google or ChatGPT for a recommendation, is your business the one that gets named?

Below you get a definition of each term, a comparison table, what the research and Google's own documentation say, and a checklist. For the basics of ordinary search, start with my guide on how a local business gets found on Google.

What do SEO, AEO, GEO and AIO mean?

All four describe your visibility when people look for answers. What differs is where the answer appears.

• SEO, search engine optimisation, is the work that makes your pages rank in the ordinary search results on Google and Bing, and helps your business show up in Google Maps.
• AEO, answer engine optimisation, is the work of becoming the direct answer: the featured snippet at the top of Google, an answer in the People also ask box, or the reply a voice assistant reads aloud.
• GEO, generative engine optimisation, is the work of being used and cited as a source when an AI writes the answer, in ChatGPT, Gemini, Perplexity or Google AI Overviews.
• AIO is ambiguous. Some people use it for AI optimisation in general, which makes it a synonym for GEO. Others use it as short for Google AI Overviews. When someone sells you "AIO", ask which one they mean.
• LLMO, large language model optimisation, is one more name for GEO, and so is "AI SEO".

Google describes a featured snippet as a result where the descriptive text is shown first, and says snippets help when you use a phone or talk to your device. Google picks snippets and People also ask answers automatically. No markup can request one.

Google AI Overviews are summaries written by AI that appear in some Google searches, with links to dig deeper. AI Mode is a separate AI search where you can ask follow up questions. As of 15 October 2026, Google's Search Help pages list Norway among the countries and Norwegian among the languages for both features.

SEO vs GEO vs AEO vs AIO: the comparison table

Most of the work overlaps: a clear page that answers real questions helps in every column. What changes is how you judge success, because an AI answer can name you without anyone clicking.

What does the research behind GEO actually show?

The term GEO comes from a research paper, "GEO: Generative Engine Optimization", by Pranjal Aggarwal and five other authors, a team that includes researchers from Princeton University. It was first published on arXiv in November 2023 and is part of the KDD 2024 conference. The authors built a benchmark of 10 000 search queries from many domains and tested how changes to a page affected how much of it ended up in AI answers.

The headline result, in the paper's own words: "GEO can boost visibility by up to 40% in generative engine responses." The changes that worked best were about credibility, not tricks:

• Citations, quotations and statistics. Adding citations to credible sources, quotations and statistics gave a relative improvement of 30 to 40 percent on the main visibility measure, which counts how many words from a source appear in the answer and how early.
• Fluent, readable text. Making the text more fluent and easier to understand gave 15 to 30 percent.
• Keyword stuffing did not work. It gave little to no improvement, and on Perplexity it performed 10 percent worse than the unchanged page.
• A more persuasive, authoritative tone gave no significant improvement.
• Smaller sites gained most. Adding citations raised visibility by 115.1 percent for websites ranked fifth in the search results, while the top ranked websites lost 30.3 percent on average.

Read the numbers with care. The researchers rewrote pages with a language model and tested them on their own test engine and on Perplexity, not on ChatGPT or Google AI Overviews. They note that the methods may need to adapt as these engines evolve, and they did not measure effects on search rankings. The study shows what kind of content AI answers like to use, not that your business will be named next week.

What stays the same: Google says it is still SEO

Google Search Central, Google's documentation for website owners, says on its page about AI features that the best practices for SEO remain relevant for AI Overviews and AI Mode, with no additional requirements or special optimisations needed. To be shown as a supporting link, a page must be indexed and eligible to be shown in Google Search with a snippet.

Google's guide to generative AI features names AEO and GEO directly and concludes that, from Google Search's perspective, this work is "still SEO". The same guide lists what you do not need to do:

• No llms.txt or other special AI files. Google says Google Search ignores them.
• No special schema.org markup. Structured data is not required, though it still helps you qualify for rich results.
• No need to chop your content into tiny pieces.
• No hunting for inauthentic mentions across the web, which Google says is not as helpful as it might seem.

What Google does recommend is familiar SEO: allow crawling in robots.txt and in your hosting or content delivery network (CDN), put important content in text, link your pages to each other, keep structured data in line with the visible text, and keep your Business Profile up to date.

What is different when an AI writes the answer?

In ordinary search you win a click. In an AI answer you win a mention, a citation or nothing, even when you rank well. Six things matter more than before:

1. Being cited, not only ranked. Google says AI Overviews and AI Mode may run several related searches across subtopics and sources to build one answer. A page that clearly answers one narrow question can be picked even if it is not first for the main search.
2. Entity clarity. An entity is a clearly defined thing: your business, with one name, one address, one phone number and a clear list of services. Use exactly the same details on your website, your Google Business Profile and in directories, so no system has to guess.
3. Answer first writing. Put the answer in the first sentence under each heading, then the details. "We take emergency jobs in Lillestrøm at weekends, from 07:00 to 22:00" is easier to quote than a paragraph about passion for quality.
4. Structured data. Not required, as Google says, but LocalBusiness markup with name, address, phone, opening hours and price range gives machines the same facts your page gives people. It must match the visible text.
5. Mentions across the web. Google notes that its AI features can show what is being said about products and services across the web. Real reviews, local press, supplier pages and industry directories all add to that picture.
6. Freshness. Google builds its AI answers on up to date pages from its search index. Old prices and opening hours work against you, so date your price pages and update them.

For a local business, the Google Business Profile is the strongest single source of facts. Google says local results are based mainly on relevance, distance and prominence, and that prominence also builds on how many websites link to your business and how many reviews you have. See my guides to Google Business Profile and to getting more Google reviews.

How do ChatGPT and Google's AI find your pages?

AI tools read the web with crawlers, and you control their access in a small text file, robots.txt, at the root of your website.

• ChatGPT finds pages for its search answers with OpenAI's crawler OAI-SearchBot. OpenAI writes that sites that block it are not shown in ChatGPT search answers, and that your web host or CDN must let the crawler through. ChatGPT ranks results by multiple factors, so no place is certain.
• ChatGPT uses your customer's location. OpenAI's own example: a question about good restaurants near me, asked in the San Francisco area, may be rewritten into the search "top restaurants San Francisco". A page that says plainly what you do and where, such as "hair salon in Lillestrøm", matches the search that is actually run.
• Google AI Overviews and AI Mode build on Google's own search index. If your page is indexed and can show a snippet, it is eligible, and Google says there are no additional technical requirements.
• Perplexity uses PerplexityBot, which Perplexity says is designed to surface and link websites in its search results.

What about llms.txt?

llms.txt is a proposal published in September 2024 by Jeremy Howard: a Markdown file at the root of a website, such as yoursite.no/llms.txt, that gives language models a short summary of the site and links to the most useful pages. It is not an official standard, and support varies. Google says Google Search ignores it. Anthropic and OpenAI publish llms.txt files for their own developer documentation, but that does not show that their assistants read yours.

My view: it is quick to write, so we have one on lysechko.com with our services, prices and contact details. Treat it as a cheap extra, never as a replacement for clear pages.

How can a local business measure AI visibility?

No tool shows every AI answer that mentions you, but three tools show the trend if you check them once a month.

1. A fixed list of prompts

Write ten questions your customers would actually ask. Ask them in ChatGPT, Gemini, Google AI Mode and Perplexity on the same day every month, with the same wording. For each answer, note four things: were you named, was your website linked, which competitors were named, and was any fact about you wrong.

2. The AI Assistant channel in Google Analytics

Google Analytics 4 has a default channel called AI Assistant, for visits from sources like ChatGPT, Gemini, Deepseek, Copilot and Grok. Open Reports, then Acquisition and Traffic acquisition, and look for the row. Google notes that the channel excludes AI Overviews and AI Mode, which count as Organic Search. Perplexity is not on Google's list of examples, so also look for chatgpt.com and perplexity.ai among your traffic sources.

3. Search Console

Google includes traffic from AI features in the ordinary Performance report in Search Console, under the Web search type. Since 31 August 2026, all websites can also open a separate Generative AI performance report with impressions in AI Overviews and AI Mode by page, country, device and date. It shows impressions only, not clicks, and a site with very few AI impressions may not see the report yet.

Also ask new customers where they heard about you. When someone answers "ChatGPT", that is the clearest signal you will get. My guide to conversion tracking shows how to measure the rest.

Checklist: what to do this week

• Write your ten test prompts, run them once in ChatGPT, Gemini, Google AI Mode and Perplexity, and save the answers.
• Open yoursite.no/robots.txt and check that it does not block Googlebot, OAI-SearchBot or PerplexityBot. Ask your web host whether its firewall blocks AI crawlers.
• Make your business name, address and phone number identical on your website, your Google Business Profile and directories such as Gule Sider and 1881.
• Write prices or price ranges, opening hours and the areas you cover in plain text on the site, not only in images or PDF files.
• Start every service page with a two sentence answer: what it is, who it is for and what it costs.
• Ask three happy customers for a Google review this week.
• Write down this month's numbers from Google Analytics and Search Console, and put a monthly reminder in your calendar to repeat the prompt check.

Do it yourself or get help?

Most of the checklist is work you can do yourself in a few evenings. What takes longer is the part that builds over months: better pages for each service and area, real mentions on other sites and a steady flow of reviews. If your website itself is the bottleneck, read how to build a website with AI without the usual mistakes.

In my SEO work for local businesses, visibility in ChatGPT and Gemini is a stated goal, next to rankings in Google and Google Maps. It costs 7 000 kr per month, minimum three months. I never promise what an AI will answer, because nobody controls that. What I do is make your business easy to find, easy to understand and easy to cite.