AIO, AEO, GEO and LLMO – the four disciplines of AI visibility, explained clearly

What lies behind the four abbreviations, why they are now relevant – and what brands can concretely do.

Table of contents

1. Why now? Three developments that make the shift tangible
2. AIO – AI Overviews: Google’s AI Summaries
3. AEO – Answer Engine Optimisation: Being the answer
4. GEO – Generative Engine Optimisation: How AI Talks About Brands
5. LLMO – Large Language Model Optimisation: Becoming Part of the AI Knowledge 
6. What Concrete Steps Brands Can Take Now
7. Sources 

Around 900 million people use ChatGPT every week (Backlinko, Dec. 2025). Perplexity processed around 780 million search queries in May 2025 – an increase of 239 percent compared with August 2024 (SEOProfy, 2025). And on Google, AI-generated summaries now appear in roughly every fifth search query (Pew Research, March 2025).

This is changing not only where users search, but also how they receive answers. Instead of ten blue links, AI systems provide a single, summarised answer. If you do not appear there, you are not clicked – and often not even noticed. This is exactly where four disciplines come in, which are grouped under the umbrella term AI visibility.

Anyone already familiar with the basic terms will find a comprehensive reference work in the Peak Ace AI Glossary 2026. This article explains the differences, connections and concrete courses of action.

Why now? Three developments that make the shift tangible

• Zero-click searches dominate: According to Similarweb, the share of searches without a click increased from 56 percent (May 2024) to 69 percent (May 2025). Zero-click means: users find the answer directly on the search results page – in featured snippets, knowledge panels or AI overviews – without visiting a website.
• Google’s market share is declining noticeably for the first time: According to StatCounter, it fell below 90 percent for the first time in 2025. ChatGPT Search processed more than one billion web searches in a peak week (OpenAI, April 2025).
• AI traffic converts better: According to a Superprompt analysis, visitors via ChatGPT or Perplexity convert five times better than Google traffic – although the study comes from the provider itself and has not yet been independently verified.

AIO – AI Overviews: Google’s AI Summaries 

AI Overviews are AI-generated summaries that Google displays directly above the organic results. Instead of a list of links, Google summarises the answer itself – based on sources it considers trustworthy.

The impact is measurable: according to Seer Interactive (September 2025), the organic click-through rate drops by up to 61 percent for searches with AI Overviews. At the same time, brands cited as a source record 35 percent more clicks. Visibility is therefore not disappearing – it is shifting toward the most trustworthy sources.

Google prioritises content with strong E-E-A-T signals: topical specialisation, demonstrable expertise, consistent brand information and structured data. 88 percent of queries that trigger AI Overviews are informational in nature (Semrush, 2025).

Key question: “Am I being used as a source in Google’s AI summaries?”

AEO – Answer Engine Optimisation: Being the Answer 

AEO aims to be the direct answer – in featured snippets, “People Also Ask” boxes, voice assistants and AI Overviews. The difference from classic SEO: instead of appearing among ten results, the goal is position zero.

In practice, this means structuring content so that AI systems can immediately extract the answer. Clear question–answer pairs, the most important information at the beginning of the paragraph, and FAQ and HowTo schema where appropriate. AEO rewards topical depth – not keyword breadth.

Practical example: An insurance company formulates its FAQ page in the way users actually ask questions – e.g. “From when does disability insurance pay out?” – and provides the answer in a maximum of two sentences. Result: three of the five most frequent questions appear as a featured snippet.

Key question: “Am I the answer – or just one of many results?”

GEO – Generative Engine Optimisation: How AI Talks About Brands 

GEO addresses a new challenge: how can you influence what ChatGPT, Perplexity or Copilot say about a brand? Generative engines do not list results – they formulate their own answers based on sources they consider relevant. GEO optimises the likelihood of being used as a source and steers brand framing.

The most comprehensive study so far comes from Aggarwal et al. (KDD 2024): content with concrete statistics and source references increases visibility in generative answers by up to 40 percent. Keyword stuffing works significantly worse in generative engines than in traditional search engines.

Concretely, this means: citable statements instead of marketing language, consistent information across all channels and the targeted development of earned media – because AI systems prefer independent third-party sources.

Key question: “Do I appear in AI answers – and how am I portrayed?”

LLMO – Large Language Model Optimisation: Becoming Part of AI Knowledge 

LLMO goes deeper. While GEO optimises the representation in AI answers, LLMO aims at anchoring within the knowledge base itself. Language models derive their knowledge from training data (static) and retrieval-augmented generation (RAG – real-time retrieval of external sources). LLMO optimises for both channels.

The difference from GEO can be summarised as follows: LLMO ensures that the AI knows a brand. GEO ensures that it describes it correctly. Without LLMO, the foundation is missing; without GEO, control over the framing is missing.

In practice, this means providing fact-based, crawlable content, not blocking AI crawlers (GPTBot, ClaudeBot, PerplexityBot) via robots.txt, keeping brand information consistent and updating content regularly.

Key question: “Am I a reliable knowledge source for the model – or do I not exist in its knowledge at all?”

What Concrete Steps Brands Can Take Now

1. Check content structure (AEO/AIO):
   Review the most important pages for clear question–answer pairs. Implement FAQ and HowTo schema. Test: search for your own brand on Google and check whether AI Overviews appear – and whether you are cited as a source.
2. Monitor AI answers (GEO):
   Regularly enter the most important target-group questions in ChatGPT, Perplexity and Gemini. Document: Is the brand mentioned? Are the facts correct? How is the framing compared with competitors?
3. Ensure crawlability (LLMO):
   Check whether AI crawlers can capture your content. Keep brand information consistent across the website, LinkedIn, industry directories and press releases.
4. Build earned media (all disciplines):
   Expert articles, guest contributions and mentions in independent comparisons strengthen citability. The goal is no longer only backlinks – but citability in AI answers.

Conclusion 

AIO, AEO, GEO and LLMO describe four perspectives on the same challenge: visibility in a world where answers are increasingly generated by AI systems. Most brands are not yet dealing with this systematically – those who start now have a real advantage. Not in months, but in quarters.

Anyone who wants to go deeper will find more than 15 additional terms in the Peak Ace AI Glossary 2026 – from AI Brand Monitoring to Hallucination to Zero-Click Search.

Sources 

• Aggarwal, P. et al. (2024): „GEO: Generative Engine Optimization.” ACM SIGKDD Conference (KDD 2024). 

• Backlinko (2026): „ChatGPT Statistics 2026″ – rund 900 Mio. wöchentliche Nutzer:innen (Dez. 2025). 

• OpenAI (April 2025): Über 1 Mrd. Web-Suchen in ChatGPT in einer Peak-Woche; zitiert in Chad Wyatt, „100+ ChatGPT Statistics for 2026″. 

• Pew Research (2025): „Google users are less likely to click on links when an AI summary appears.” – 18 % aller Google-Suchen mit AI Summary (März 2025). 

• Seer Interactive (2025): „AIO Impact on Google CTR: September 2025 Update.” – CTR –61 %, zitierte Marken +35 %. 

• Semrush (2025): 88 % der Queries, die AI Overviews auslösen, sind informationaler Natur. 

• SEOProfy (2025): „Perplexity AI Statistics” – 780 Mio. Suchanfragen im Mai 2025 (+239 % gg. Aug. 2024). 

• Similarweb (2025): Zero-Click-Suchen 56 % → 69 % (Mai 2024 – Mai 2025). 

• StatCounter (2025): Googles Suchmaschinen-Marktanteil erstmals unter 90 %. 

• Superprompt (2025): „Zero Click Search Worsens” – KI-Traffic konvertiert 5× besser (herstellereigene Analyse).