AI Search 101 · Search Engine Optimization
What is SEO?
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Search Engine Optimization (SEO) is the practice of helping search engines crawl, understand and rank a website's pages, so they appear — and get clicked — when people search for what the site offers, including in the AI answers search engines now show.
Google still accounts for about 90% of search engine use worldwide[1] and more than 5 trillion searches a year.[2] What has changed is the results page: AI Overviews and AI Mode now answer many questions directly, and Google says optimizing for them is still SEO.[3]
Key takeaways
- SEO is how pages get found: crawled, indexed and ranked by search engines, and clicked from the results.
- It is also how pages get into Google's AI answers. AI Overviews and AI Mode only use pages that are indexed and eligible to show a snippet.[4]
- Search is still the largest channel by far: AI chatbots sent 0.28% of total web traffic in March 2026, across 74,752 sites Ahrefs measured.[5]
- But fewer searches end in a click: 68% of US Google searches ended without one in early 2026.[6]
- Ranking no longer guarantees being cited. Only 37.9% of the URLs cited in AI Overviews also ranked in Google's top 10 in early 2026.[7]
What does SEO stand for?
SEO stands for Search Engine Optimization.
- SearchA person types or speaks a query and gets back results — links, and increasingly an AI-generated summary above them.
- EngineGoogle, Bing and the rest crawl the web, index what they find and rank it for each query. Google accounted for 89.94% of search engine use worldwide in September 2026.[1]
- OptimizationMaking pages easy to crawl, clearly relevant to the query, useful to the reader and worth linking to.
How does SEO work?
Google describes search in three stages: crawling, where automated programs fetch pages; indexing, where Google analyzes what each page is about and stores it; and serving, where it returns the most relevant indexed pages for a query.[8]
Google's AI features sit on top of the same pipeline. AI Overviews and AI Mode draw on pages in Google's index: a page has to be indexed and eligible to show a snippet, and its site not opted out in Search Console, to be used — so the pages SEO gets indexed are the pages Google's AI answers can cite.[3,4]
Crawling
Googlebot and other crawlers find pages through links and sitemaps and fetch them. A page that's blocked or unreachable isn't fetched.
Indexing
The engine renders the page, works out what it's about and decides whether to store it. Duplicates and thin pages may be left out.
Serving
For each query, the engine ranks indexed pages by relevance and quality and decides which features to show — including AI Overviews.
SEO vs AEO: what's the difference?
Google counts AEO and GEO as part of SEO.[3] The difference is what you aim for and what you measure.
| Dimension | SEO | AEO |
|---|---|---|
| Goal | Rank pages and earn the click | Be named, cited or recommended inside an AI answer |
| Where it shows | Google, Bing and other search results pages | ChatGPT, AI Overviews, AI Mode, Perplexity, Gemini, Claude, Copilot |
| Success looks like | A top position and organic traffic | A mention, a citation or a recommendation |
| Measured with | Search Console, Bing Webmaster Tools and analytics | The same questions asked of each AI engine, plus Google's and Bing's new AI reports[9,10] |
| Depends on the other? | No — it stands on its own | Yes — answers grounded in search can only use pages that are found and indexed |
What still moves SEO in 2026
Google's advice for AI search is its advice for search: make something people find useful, and make it easy to find.[3,11]
Crawlable, indexable pages
If a page isn't crawled and indexed, it can't rank — or appear in AI Overviews.[4]
Helpful, original content
Google's guidance for classic and AI results alike is unique, non-commodity content written for people.[11]
Page experience
A page that loads quickly and displays well on every device is part of what Google recommends for its AI experiences too.[11]
Links and reputation
Links and mentions from credible sites help engines decide which pages to trust, and give AI answers a second source for what you claim.
Structured data, matched to the page
Schema markup still qualifies pages for rich results. But Google stopped showing FAQ rich results on May 7, 2026,[12] and says AI features need no special markup.[3]
Answers near the top
Put the answer to the query where the reader lands, in plain words, with the specifics behind it. It is what both a searcher and an AI answer are looking for.
SEO by the numbers
Search is still the largest discovery channel — and the results page is the part changing fastest.
- 89.94%of search engine use worldwide was Google's in September 2026StatCounter, Sep 2026 [1]
- 5T+Google searches a year, by Google's own countGoogle, Mar 2025 [2]
- 0.28%of total web traffic came from AI chatbots in March 2026Ahrefs, May 2026 [5]
- 68%of US Google searches ended without a click in early 2026SparkToro, Jun 2026 [6]
SEO basics that also serve AI search
Check what's indexed
Use Search Console's page indexing report to confirm your important pages are indexed, and fix the reasons the rest aren't.
Answer the query on the page
Put the answer near the top, in plain words, and support it with specifics.
Keep pages fast
Test your key pages' speed and Core Web Vitals, and fix what delays the main content.
SEO questions, answered
What does SEO stand for?
SEO stands for search engine optimization: the practice of helping search engines crawl, understand and rank a site's pages so they appear, and get clicked, when people search.
Is SEO dead because of AI?
No. Google still accounts for about 90% of search engine use worldwide, and Alphabet said in July 2026 that its AI features are driving growth in search queries. AI answers do take clicks — 68% of US Google searches ended without one in early 2026, per SparkToro — but Google's AI features are built on its search index, so SEO is how pages get into them.
Does SEO help with AI search?
Yes. Google's AI Overviews and AI Mode use pages from its search index: a page needs to be indexed and eligible to show a snippet, and its site not opted out in Search Console, to appear in them. Google's 2026 guidance says optimizing for its generative AI features is still SEO.
What's the difference between SEO and AEO?
SEO aims to rank pages and earn clicks from search results; AEO aims to have a brand named, cited or recommended inside AI answers, on Google and on engines like ChatGPT and Perplexity. They share most of their foundations, and Google counts AEO as part of SEO.
If I rank in Google, will AI answers cite me?
Not reliably. In Ahrefs' early-2026 study, only 37.9% of the URLs cited in AI Overviews also ranked in Google's top 10, and in its 2025 study only 12% of links cited by ChatGPT, Gemini and Copilot appeared in Google's top 10. Ranking helps a page get found; being cited is a separate outcome worth measuring.
Does structured data still matter for SEO?
Yes, for the rich results it still powers, as long as it matches what the page shows. But Google stopped showing FAQ rich results on May 7, 2026, and says no special structured data is needed for AI Overviews or AI Mode.
How long does SEO take?
Usually months, not days. A change only counts once Google has recrawled and reindexed the page, and rankings for competitive queries rest on a reputation that builds over time. Google's guidance on hiring an SEO suggests asking what results to expect, and in what timeframe.
Sources
Every figure on this page was checked against its source on .
- 1.StatCounter. Search engine market share worldwide. Sep 2026.
- 2.Google. AI, personalization and the future of shopping. Mar 2025.
- 3.Google Search Central. Optimizing your website for generative AI features on Google Search. May 2026, updated Jul 2026.
- 4.Google Search Central. AI features and your website. Dec 2025.
- 5.Ahrefs. AI Chatbot Traffic: What It Is, and How to Get More. May 2026.
- 6.SparkToro. In 2026, Less than One Third of Google Searches Still Send a Click. Jun 2026.
- 7.Ahrefs. Update: 38% of AI Overview Citations Pull From The Top 10. Mar 2026.
- 8.Google Search Central. In-depth guide to how Google Search works. Dec 2025.
- 9.Google. New opportunities, control and insights for website owners. Jun 2026, updated Aug 2026.
- 10.Microsoft Bing. Introducing AI Performance in Bing Webmaster Tools Public Preview. Feb 2026.
- 11.Google Search Central. Top ways to ensure your content performs well in Google's AI experiences on Search. May 2025.
- 12.Google Search Central. Deprecating the FAQ rich result feature. May 2026.
- 13.OpenAI. Overview of OpenAI Crawlers. 2026.
- 14.Anthropic. Does Anthropic crawl data from the web, and how can site owners block the crawler?. Apr 2026.
- 15.Perplexity. Perplexity Crawlers. Jan 2026.
- 16.Alphabet. Alphabet Announces Second Quarter 2026 Results. Jul 2026.
- 17.Google Search Central. Do you need an SEO?. Jun 2026.
- 18.Ahrefs. Only 12% of AI Cited URLs Rank in Google's Top 10 for the Original Prompt. Aug 2025.