SEO vs GEO vs AEO — What the Acronyms Mean and What Actually Changed

If you’ve been pitched “GEO” or “AEO” as something you need on top of SEO, you’re being asked to pay for a new acronym, and it’s fair to want to know whether there’s anything behind it. There is — a little. The rest is a naming exercise. Here is where each term came from, what Google says, what genuinely changed, and how to tell a real service from a relabelled one.

Where the terms came from

SEO — search engine optimization — has meant the same thing for twenty-five years: making a website rank in search results. Its foundation is crawlable pages, genuine content, technical health, and the links and signals that establish prominence.

AEO — answer engine optimization — is marketing shorthand from the featured-snippet and voice-assistant era, roughly 2017 onward. It means structuring content so a system can extract a direct answer: a clear question, a concise answer, supporting detail. It described a page style more than a discipline, and as the extraction surfaces changed, the term drifted.

GEO — generative engine optimization — has a precise origin. A research paper titled “GEO: Generative Engine Optimization,” by Pranjal Aggarwal and co-authors, appeared on arXiv in November 2023 and was presented at KDD 2024. It tested how changes to content affected visibility in generative search engines — systems that write an answer and cite sources. Vendors adopted the term within months. There is no consensus definition beyond the paper’s; “LLMO,” “AIO,” and “AI SEO” circulate alongside it meaning roughly the same thing.

So: one established discipline, one page-style label, and one academic coinage that became a product category.

What Google says

Google’s guidance on optimizing for its generative AI features, published in 2026, doesn’t use the acronyms. Its position is that, from Google Search’s perspective, optimizing for generative AI search is optimizing for the search experience, and thus still SEO. Google’s search liaison has put it more bluntly in public: good SEO is good GEO. The same guidance says no special files, no special markup, and no special writing style are required for AI Overviews or AI Mode. (How to Show Up in Google AI Overviews and AI Mode walks through the whole document.)

Microsoft uses the term GEO in its own materials and ties eligibility to the same fundamentals. OpenAI, Perplexity, and Anthropic don’t define an optimization practice at all; they publish crawler documentation and leave the rest to the quality of what they find.

What actually changed

The acronyms describe output surfaces, not disciplines:

The foundation doesn’t change across the rows; the reward shifts a little toward the right. That shift is real, and it comes down to three things:

Quotability. A generated answer about implant dentists in Mesa quotes the page that says what the treatment involves, roughly what it costs, and who provides it. It skips the page that says “restore your confidence.” That was always good practice; it’s now visibly rewarded.

Entity clarity. Generative systems assemble a picture of your business from many sources. If your name, services, and area are described consistently — on the site, the Business Profile, the directories — the picture is sharp and the citation is accurate. If they disagree, the system either skips you or describes you wrong.

Crawler access across companies. Ranking meant Googlebot. Being cited means OAI-SearchBot, PerplexityBot, Claude-SearchBot, and Bingbot too — and the CDN and firewall settings that quietly block them. How AI Crawlers Find Your Website has the table.

That’s the whole substantive difference. It’s worth doing. It isn’t a new profession.

What didn’t change

• The foundation. Crawlable, indexable, unique, genuinely useful content. Every official source converges on it.
• The importance of Google and Bing. Most AI search systems lean on or resemble those indexes; a site invisible to them is invisible upstream.
• The absence of a formula. No company publishes how it selects citations. Answers vary between sessions. A promise of placement — in a ranked list, an extracted answer, or a generated response — is a promise nobody can keep.
• The uselessness of tricks. Special files, special markup, keyword-stuffed Q&A blocks. Google says none are required; measurement finds none produce uplift. What Schema Markup Does (and Doesn’t Do) covers the markup evidence in detail.

How to tell a real service from a relabelled one

Ask what, specifically, they will do. A real answer names concrete work:

• An entity consistency audit — name, services, area, categories — across the site, Business Profile, and directories, with the fixes.
• A crawl-access audit — robots.txt, CDN bot settings, firewall rules — for every search bot that matters, with the fixes.
• Answer-shaped pages — plain quick answers and real FAQs on service pages, stating facts a system can quote.
• Measurement in the first-party reports that now exist: Search Console’s Generative AI report and Bing Webmaster Tools’ AI Performance report, plus a logged monthly check of what the assistants actually say.
• An honest statement that placement can’t be promised.

A relabelled service leads with the acronym, promises “AI rankings,” sells an llms.txt file as a deliverable, and can’t say what it would do that good SEO doesn’t already require.

We sell AI search optimization under a plain name and describe it in exactly those concrete terms, because the work is real and the acronyms aren’t. If you’d like to understand the shift before deciding anything, How AI Search Changes Website SEO explains it without selling it; if you’d like to know whether your site is even eligible — indexed, ranking, legible — Why Isn’t My Website Ranking on Google? is the place to start, because nothing downstream works without it.