The terms come from different moments. SEO is the long-standing practice for search results. AEO describes writing for answers. GEO describes aiming at generative AI tools. None is an official standard.
Our glossary defines the newer terms in plain words, for example answer engine optimization; this guide compares them and says what to do about the overlap.
What does each term mean?
- SEO (search engine optimization): improving a site so that search engines can find, understand and rank its pages in the ordinary results.
- AEO (answer engine optimization): writing and structuring pages so a search engine or assistant can lift a clear answer from them. See our AEO entry.
- GEO (generative engine optimization): making a brand and its pages easier for generative AI tools to find, understand and mention. See our GEO entry.
- LLM SEO and AI SEO: other names for much the same thing. AI SEO can also mean using AI tools to do SEO work, so check which one a person means.
None of these is defined by a search engine. They are industry labels, and different people draw the lines in different places. That is why advice under these names often contradicts itself.
What is the same work?
Google says that its AI features in Search follow the same SEO best practices, that there are no additional technical requirements, and that no special markup or AI text files are needed. Its May 2025 post lists the advice: unique, helpful content, a good page experience, no accidental blocking of Googlebot, accurate structured data, and attention to the overall value of visits.
In practice the shared work is the larger part: pages that answer the question, facts that are accurate and dated, named authors, fast and readable pages, sound internal links, and a site that search crawlers can reach. A business that does these well has done most of what any of the three labels asks.
What is genuinely different?
Four things differ, and they are about emphasis and measurement more than technique.
- The surface. Classic SEO aims at a ranked list of links. AEO and GEO aim at being the source an answer is built from, which may be shown with a link or may not.
- The crawlers. Each engine has its own. OpenAI documents OAI-SearchBot for ChatGPT search and a separate GPTBot for training. Perplexity documents PerplexityBot for surfacing and linking sites. Google uses Googlebot. Decide on each one separately.
- The measurement. Rankings and clicks are less complete when an answer ends a search. Pew Research found clicks on a result link in 8% of visits with an AI summary, against 15% without. So calls, sign-ups and mentions matter more.
- Off-site presence. Generative tools may draw on what is said about a business elsewhere. The engines do not document this, so treat it as plausible and untested, and keep company details consistent everywhere as ordinary good practice.
Sources for the crawler points: OpenAI and Perplexity, read 12 November 2026. Pew Research: 22 July 2025, read 8 November 2026.
Which one should you invest in?
Start with the shared work, because it helps every label. If your site is slow, thin, hard to crawl or inconsistent about basic facts, no acronym will fix that. Our technical audits find these faults.
Then add the AI-specific layer: check which crawlers you block, make your key pages answer first, and set up measurement beyond clicks. Our guide to tracking AI search visibility shows how. The pillar guide on how to optimize for AI search covers the engines one by one.
What should you be careful about?
Be careful with anyone who sells GEO as a separate secret system, promises citations in named tools, or quotes exact ranking factors for a model. The engines do not publish them. Be careful too with mass-producing pages to cover every question: Google's spam policies treat many pages made mainly to manipulate rankings as scaled content abuse, whether or not AI wrote them.
Conclusion
SEO, AEO and GEO describe overlapping work with different emphasis. Do the shared work first, add crawler and measurement choices for AI engines, and ignore promises that rest on unpublished rules.
PromotEdge International is an international strategy, technology, marketing and design company, and our delivery team is in India. See our AI search service.
Facts we rely on: see our company facts for what we state about ourselves and where each fact comes from.