AI SEO is the practice of making a site’s content retrievable, quotable and accurately represented by systems that generate answers rather than return links (e.g., ChatGPT Search, Google AI Overviews, Perplexity, Claude and Microsoft Copilot). These systems work by retrieval-augmented generation: a query triggers a search against an index or a live crawl, a handful of sources are retrieved, and a language model synthesizes an answer from them, usually with citations. Visibility therefore depends on two separate things: being retrieved at all, and being written in a way that survives summarization.
Two named sub-disciplines sit underneath it and overlap heavily without being identical. Generative engine optimization (GEO) concerns presence and framing inside a synthesized response (whether your brand is part of the answer at all, and how it is characterized). Answer engine optimization (AEO) concerns being the source quoted for a specific question, and descends directly from featured snippet and People Also Ask work. The discipline is young, the measurement is unstable, but the fundamentals are still recognizably SEO.