SEO, AEO and GEO: What Are They?

The three acronyms point at three different targets within online search. SEO (Search Engine Optimization) works to push a page higher in a search engine’s list of results: carefully chosen keywords, internal and external links, technical factors like page speed. It’s the oldest of the three disciplines and remains the common ground AEO and GEO both build on.

AEO (Answer Engine Optimization) changes the finish line. Per Seobility’s definition, it aims to place content directly inside a direct answer — a box at the top of the results, a reply read out by a voice assistant — without the user ever clicking a link. Where SEO measures success in rankings and clicks, AEO measures it in presence inside the answer itself.

GEO (Generative Engine Optimization) is the newest of the three. The term comes from an academic paper — “GEO: Generative Engine Optimization,” by Pranjal Aggarwal and colleagues at Princeton, Georgia Tech and the Allen Institute for AI — submitted to arXiv in November 2023 and published in the proceedings of the ACM SIGKDD 2024 conference. The authors describe GEO as the first paradigm built to help content creators improve their visibility inside the responses of a generative engine, a system that uses a language model to gather information from multiple sources and summarize it into a single answer. In their experiments, on a benchmark called GEO-bench, some strategies pushed content visibility up by as much as 40% — a lab result, not a real-world adoption statistic, worth keeping separate when it’s cited.

Practical example: a school writes a guide on how photosynthesis works. With SEO done well, the guide ranks among the top results when someone searches “how does photosynthesis work.” With AEO done well, the same guide gets read out by a voice assistant as the direct answer to “how does photosynthesis work?” With GEO done well, a chatbot summarizing the topic cites the guide as one of the sources behind its answer.

Not every source draws the same line between AEO and GEO. Seobility, for instance, treats them almost as synonyms, alongside labels like “AI optimization,” arguing they describe the same underlying practice. The academic paper that coined GEO, on the other hand, treats it as a discipline in its own right, with its own evaluation benchmark and specific experimental goals. In practice AEO and GEO share the same direction — getting noticed by a system that generates an answer instead of simply listing links — but not everyone in the industry treats them as identical.

Google, for its part, has a clear position on how its AI-powered features relate to SEO. According to Google Search Central, there are no extra requirements or special optimizations needed to appear in AI Overviews or AI Mode: no new machine-readable files, no dedicated markup. What’s needed, as a baseline, is a page that’s indexed and eligible to appear in ordinary search results, with a readable snippet. Google adds that every fundamental of existing SEO still applies: robots.txt, internal links, a page’s browsing experience, text content, structured data.

The mechanism behind AI Overviews and AI Mode helps explain why SEO fundamentals stay useful. According to Google Search Central and the official blog post that announced AI Mode on March 5, 2025, both features rely on a technique called “query fan-out”: the system issues multiple related searches across different subtopics and data sources, then merges the results into a single, easier-to-read answer. To make it into that synthesis, content first has to pass through the ordinary search sieve — the same indexing, the same technical eligibility SEO has always tended to.

Numbers on AI-driven search adoption keep climbing fast. Google reported, as of March 5, 2025, more than a billion people using AI Overviews; by the Google I/O keynote on May 19, 2026, the reported number had grown to more than 2.5 billion monthly users. Over the same period, a SparkToro study based on Similarweb data measured a rising share of “zero-click” searches: around 68% between January and April 2026, up from about 60% in 2024, a rise SparkToro links directly to the spread of AI Overviews. A third figure often circulates alongside these two — that by 2026 a quarter of organic traffic could shift to chatbots and assistants — and it’s a forecast, not a measurement: Gartner published it on February 19, 2024, and by late 2026 several independent trackers note that Google still holds more than 90% of search market share, a sign the predicted drop hasn’t played out at the scale forecast. It should be read as a forecast that has only partly held up, not as something that has already happened.

For anyone running a site, three links can help map the ground SEO, AEO and GEO share: how artificial intelligence generates answers in the first place, what sets generative AI apart from other kinds of AI, and how an algorithm — including a search engine’s — decides what to show first.