Optimising content so answer engines, such as featured snippets, Google's AI Overviews and AI Mode, ChatGPT and voice assistants, use it as the direct answer to a question. Where classic SEO competes for a ranking position, AEO competes for the citation inside the answer itself.
AEO is the older idea, rooted in featured snippets and voice search, and it focuses on the question-and-answer unit. The engine works out what is being asked, retrieves candidate pages from an index and picks the passages that answer the question directly.
Four things decide which passage is picked: relevance to the exact question, directness, extractability (clean headings, paragraphs, lists and tables) and trust. Because pages linked in AI Overviews and AI Mode must be indexed and eligible for a snippet, AEO starts with crawling and indexing.
Example
Under the heading "What is citation share?", the first sentence reads "Citation share is the percentage of AI-generated answers for a set of queries that cite a given domain." It still makes sense when quoted on its own, and everything after it is supporting detail.
Related terms
Where seodada covers it
The AEO guide shows how to find the questions people ask and how to structure each answer. Keyword Research surfaces question keywords, and AI Visibility shows whether AI answers cite you for them.