What GEO is,
and where the term came from.

The definition

Generative engine optimization (GEO) is the practice of increasing how often, and how prominently, a source is cited in the responses of generative engines: AI systems that combine a large language model with retrieval from the live web to write a synthesized, cited answer to a question.

The term was introduced in November 2023 by Pranjal Aggarwal and co-authors from Princeton University, Georgia Tech, the Allen Institute for AI and IIT Delhi, in a paper titled simply "GEO: Generative Engine Optimization," later published at KDD 2024 (Aggarwal et al., "GEO: Generative Engine Optimization", KDD 2024 (arXiv 2311.09735)). They coined "generative engine" for the new kind of search engine and "GEO" for the new kind of optimization it would need.

What the research found

The authors built a benchmark of diverse questions (GEO-bench), took the source pages a generative engine would draw on, applied a set of content changes to each, and measured how much visibility the changed page gained in the engine's answer. Three findings matter for anyone doing this work:

• The best methods improved visibility by up to 40 percent in the engine's responses.
• The methods that worked were about substance: adding statistics, adding quotations from relevant sources, citing sources, and writing more fluently and clearly.
• Keyword stuffing made things worse. The tactic that defined a decade of bad SEO lowered visibility in generative answers.

What the research did not test

Read the paper before you buy a GEO package built on it. The benchmark is made of informational questions answered from web pages: the kind a student or a shopper asks. It did not test "who is the best dentist in High Point," it did not test Google Business Profile data, and it did not test reviews. The engines it measured were research setups and Perplexity, not Google AI Overviews, which did not exist at scale yet. The findings generalize in spirit (specific, sourced, clearly written content gets cited) and should not be quoted as a promise about local recommendations.

GEO, AEO and SEO side by side

In 2026 the three labels overlap almost completely, and Google's position is that all of it "is optimizing for the search experience, and thus still SEO" (Google Search Central, "Google's guide to optimizing for generative AI features" (May 2026, updated Jul 2026)). The useful distinctions are about emphasis:

Our rule of thumb: if it asks for money or a click, we call it AI SEO, because that is what business owners call it. If it teaches, we use AEO, because the acronym genuinely expands to what the work is. GEO we use when we are talking about the research or about content specifically.

What GEO looks like for a business that is not a publisher

The paper studied articles. A plumber, a law firm or a clinic can apply the same findings without starting a blog:

1. Put real numbers on your pages. Years in business, jobs completed, response time, the price range you are willing to state, the license number. "Statistics" in the paper means specific, checkable figures, not marketing math.
2. Quote real people. A named customer review, a line from the owner, a sentence from the lead technician. Quotations were among the strongest methods measured.
3. Cite your sources. When you state a fact about your industry, link to where it came from: a manufacturer spec, a state licensing board, a study. It signals the page was written by someone who knows, and it gives the engine a reason to trust the rest.
4. Write plainly. "Fluency" in the paper is clear, readable prose. Short sentences, one idea each, the answer first.
5. Then do the AEO fundamentals. None of the above helps if the page cannot be crawled, the business has three phone numbers, or the reviews only exist inside a script. The setup guide is the order of operations.

Why it matters now

Generative engines are no longer a research setup. OpenAI reported more than 900 million weekly ChatGPT users in February 2026 (Search Engine Land, "OpenAI: ChatGPT now has 900 million weekly active users" (Feb 2026)). Google's AI Overviews reached 2.5 billion monthly users and AI Mode passed one billion in May 2026 (CNBC, Sundar Pichai: AI Overviews now has over 2.5 billion monthly users (May 19, 2026); Google, Search at I/O 2026 (May 2026)). Pew found that when Google shows an AI summary, users click a traditional result on 8 percent of visits instead of 15 (Pew Research Center, "Google users are less likely to click on links when an AI summary appears" (Jul 2025)), and Ahrefs measured a 58 percent lower click-through rate for the top-ranking page when an AI Overview is present, on December 2025 data (Ahrefs, AI Overviews click study update: 58% lower CTR for the top-ranking page (Dec 2025 data, published Feb 2026)). The click you used to earn by ranking is increasingly replaced by the mention you earn by being cited. That is what GEO is about.

Straight answers about GEO

1. Aggarwal et al., "GEO: Generative Engine Optimization", KDD 2024 (arXiv 2311.09735)
2. Google Search Central, "Google's guide to optimizing for generative AI features" (May 2026, updated Jul 2026)
3. Search Engine Land, "OpenAI: ChatGPT now has 900 million weekly active users" (Feb 2026)
4. CNBC, Sundar Pichai: AI Overviews now has over 2.5 billion monthly users (May 19, 2026)
5. Google, Search at I/O 2026 (May 2026)
6. Pew Research Center, "Google users are less likely to click on links when an AI summary appears" (Jul 2025)
7. Ahrefs, AI Overviews click study update: 58% lower CTR for the top-ranking page (Dec 2025 data, published Feb 2026)

DiamondBack scan scores measure what AI systems can read on a website (a 20-point technical check), not how often a business is cited. Third-party figures are quoted from the linked studies as published.