Search Engine Optimization
Search Engine Optimization is the practice of improving the visibility of websites and information in search results. In AI search it remains foundational, because generative and answer systems still draw on the same crawling, indexing and quality infrastructure.
Why it still matters
Every acronym in this A to Z sits on top of the same substrate. If a page cannot be crawled, is not indexed, or is judged low quality, no amount of answer-engine work will rescue it, because it never enters the candidate set.
Google's 2026 guidance makes this its central point: AI Overviews and AI Mode are rooted in the same ranking and quality systems as classic Search.
Where it stops being enough
Search engine optimisation stops being enough where ranking ends and citation begins, because ranking is a document judgement. Citation is a source judgement, made on corroboration, quotability and entity resolution that the ranking systems never had to weigh.
That gap is the whole reason this vocabulary exists. It is also why the honest framing is layer rather than replacement: everything here is additional work on top of SEO that is already correct.