The three acronyms describe one job. Agencies sell them as three separate products. On the page, they want the same things.
The three terms
SEO, search engine optimisation, is the work of ranking a page in the list of results Google shows. It rewards a page that matches the search, loads fast, links to and from related pages, and earns links from other sites.
AEO, answer engine optimisation, is the work of getting a passage lifted onto the results page itself. That means a featured snippet, a People Also Ask box or a Google AI Overview. It rewards a question heading followed by a direct answer.
GEO, generative engine optimisation, is the work of getting cited by an AI assistant that writes its own answer. ChatGPT, Gemini, Perplexity and Copilot all do this. It rewards a page that states facts plainly, with a source, on a site that covers the topic in depth.
What they share
Every one of them starts with the question a real person asks, in their words. Every one of them rewards a page that answers it in the first sentences, then earns the reader’s trust with detail and sources. Every one of them reads structured data, such as FAQ and Article markup, to understand what the page is.
Google says as much. Its guidance on AI features points back to the same helpful content advice it gives for ordinary ranking. There is no separate playbook to buy.
Where they differ
Three places, and each is small.
Crawler access. Google crawls your site already. ChatGPT, Perplexity and the others use their own crawlers, and a robots.txt file written years ago can block them without anyone knowing. OpenAI lists its crawler in the GPTBot documentation. Check the file before you do anything else.
Mentions off your site. AI assistants lean more on how often a brand is named across the web, in directories and reviews. Google leans more on links. A business with a consistent name, description and category everywhere gets cited more often.
Measurement. Google Search Console shows SEO and AEO results. It does not show ChatGPT citations. For those you need a tool such as Ahrefs, which counts AI answers by platform. Our Gridly case study shows the split for one site.
What to do first
Pick the ten questions your customers ask most. Write one page for each, with the question as the heading and the answer in the first two sentences. Cite a source for every number. Link the ten pages to one parent page and to each other. Check robots.txt. Then measure in Search Console and Ahrefs.
That is SEO, AEO and GEO, done once. If you want it built for you, the method is on our AI SEO agency page.