How AI Search Engines Work | 1.1. AEO Course by Ahrefs

In this video, you’ll learn how AI search engines work under the hood which is critical in learning how to rank in AI search.

Additional Resources:
► https://www.youtube.com/watch?v=6NFei1FbytM
► https://www.youtube.com/watch?v=gReszNnykpg
► https://www.youtube.com/watch?v=xsVTqzratPs

In this first lesson, Sam Oh breaks down how AI search engines actually find, evaluate, and cite content. You will see the two sources that power AI answers, training data and real-time retrieval, and why both matter for your brand. We unpack RAG, how tools like ChatGPT, Google’s AI Mode, and Perplexity pull fresh information via web search APIs, and how classic SEO skills like ranking, earning backlinks, and publishing quality content directly influence what gets retrieved and cited.

You will also learn how query fan-out flips search from one-to-one to one-to-many. A single prompt can explode into dozens of long-tail sub-queries running in parallel, then get merged into one response. We will show how covering an entire topic, not just a single keyword, increases your odds of inclusion. You will see how to use Ahrefs’ Brand Radar AI Responses report to view fan-out queries for ChatGPT and Perplexity, and why these synthetic, inconsistent queries are a lens for topic coverage, not a new keyword list.

Finally, we dig into how AI decides who to cite. AI citations are probabilistic, not fixed positions, so we focus on AI visibility, not rankings. You will see the patterns that move the needle, consensus across the web, freshness that skews newer than traditional SERPs, and authority that gives already-ranking pages a head start. We share data like how a majority of AI Overview citations come from pages already in Google’s top 10, yet meaningful citations still come from pages outside the top 100, which means real opportunity if you play the AEO game right.

If you want your brand mentioned more often in AI Overviews and ChatGPT answers, this is the mental model you need. Press play to lock in the foundation that makes every strategy in the rest of the course make sense.