What is an AI Overview?
An AI Overview is the AI-generated summary Google shows above the traditional results for some searches, produced by its Gemini models from pages retrieved for that query. It answers the question directly and links to a selection of the sources it drew on.
Google began testing the format as the Search Generative Experience in 2023 and rolled it out as AI Overviews from May 2024, reaching the UK later that year. The mechanics, as far as Google has described them, are retrieve-then-generate: the query triggers retrieval from Google's index, a customised Gemini model synthesises a summary, and a set of source links appears alongside. Exactly which queries trigger an Overview and how sources are chosen is not public, so any confident claim about the selection algorithm should be treated with suspicion.
The commercial significance is position. An AI Overview sits above the first organic result, so when one appears, every traditional listing moves down and some users never scroll past the summary. Being cited inside the Overview therefore becomes a visibility goal in its own right, distinct from ranking underneath it. Google has since added AI Mode, a fully conversational search tab, which pushes the same logic further.
An AI Overview is not a featured snippet. A snippet quotes one page verbatim; an Overview synthesises several sources into new text, which means your content can shape an answer without being quoted or linked, and the same query can cite different sources on different days.
On earning inclusion, Google's public guidance is that normal SEO applies and there is no special markup to opt in. In practice, pages that answer the question directly, rank reasonably well and are easily crawlable seem more likely to be cited, but nobody outside Google can verify how sources are weighted.