AEO & GEO glossary: Ai search terms, explained plainly.

Core concepts

AEO (answer engine optimization)

The work of making your content the best direct answer to a specific question, so that featured snippets, voice assistants and Ai summaries use it, ideally with your name and a link attached. Learn more.

GEO (generative engine optimization)

The work of getting your business retrieved, cited and recommended by generative Ai engines such as ChatGPT, Gemini, Perplexity, Claude and Google’s Ai Overviews. Learn more.

SEO (search engine optimization)

The work of helping search engines find, understand and rank your pages so that people click through from search results. It is the foundation AEO and GEO are built on. Learn more.

Ai visibility

How often, and how favorably, Ai engines mention, cite or recommend a business when people ask the questions its buyers ask. Learn more.

Answer engine

Any system that responds to a question with an answer rather than a list of links: featured snippets, voice assistants, Ai chat assistants and Ai summaries in search.

Generative engine

An answer engine that writes a new response with a large language model, often after searching the web, rather than quoting a single page. ChatGPT, Gemini, Perplexity and Claude are examples.

Zero-click search

A search where the person gets what they need from the results page or Ai answer and doesn’t click through to any website. Being named in the answer matters more when clicks are rarer.

How Ai engines work

Large language model (LLM)

The kind of Ai model behind ChatGPT, Gemini, Claude and similar tools. It is trained on large amounts of text and generates answers word by word.

Training data

The text a model learned from before release. Brands mentioned often and consistently across the public web are more likely to be “known” to a model even without a live search.

Knowledge cutoff

The date after which a model’s training data ends. For anything newer, or anything local and current, engines rely on a live web search.

Retrieval-augmented generation (RAG)

A method where the engine first retrieves relevant pages, usually through a web search, and then writes its answer from them. Most recommendation and local answers work this way. Learn more.

Grounding

Tying an Ai answer to retrieved sources so its claims can be checked, typically shown as citations or links.

Query fan-out

When an engine splits one question into several related searches, runs them together and combines the results. Google describes this technique for its Ai features. Learn more.

Hallucination

An Ai answer that states something false with confidence, such as wrong hours or a service a business doesn’t offer. Clear, consistent facts across the web reduce the risk.

Google Ai Overviews

The Ai-generated summaries Google shows above some search results, with links to the pages it drew from. Learn more.

Google Ai Mode

Google’s conversational search experience, where people ask follow-up questions and get Ai-written answers with links.

Signals and trust

Entity

A distinct, identifiable thing, such as a business, person, place or product, that search and Ai engines can recognize and describe. Clear entity facts help engines say who you are with confidence.

Knowledge graph

A database of entities and the relationships between them, used by search engines to understand and display facts about businesses, people and places.

Citation (in Ai answers)

A link or source reference an Ai engine shows alongside its answer. Your page can be cited even when your business isn’t named, and you can be named without being cited.

Brand mention

Any time another site names your business, linked or not. Mentions on trusted lists, directories, press and forums help Ai engines treat you as a real, notable option.

Backlink

A link from another website to yours. Backlinks help your pages get discovered and ranked, and the pages that link to you are often the same sources Ai engines read.

Reviews

Customer ratings and written feedback on platforms like Google, Yelp and industry directories. Volume, recency and specific detail all give engines evidence to repeat.

Consensus

Agreement across independent sources. When several trusted sites describe a business the same way, an Ai engine can state it as fact; one source on its own is just a claim. Learn more.

NAP consistency

Keeping your business name, address and phone number identical everywhere they appear online. Conflicting details make engines less confident about which facts are right.

E-E-A-T

Experience, Expertise, Authoritativeness and Trustworthiness: the qualities Google’s search quality rater guidelines use to describe helpful, reliable content.

Technical

Structured data (schema markup)

Code on a page, usually JSON-LD using the Schema.org vocabulary, that describes the business, service, article or FAQ in a machine-readable way. It should always match what visitors can see.

robots.txt

A file at the root of a website that tells crawlers which parts of the site they may access. A rule that blocks an Ai crawler can keep your pages out of that engine’s answers.

Ai crawler

A bot that fetches web pages for an Ai company, either to power live Ai search (such as OAI-SearchBot or PerplexityBot) or to collect training data (such as GPTBot). They are usually controlled separately in robots.txt. Learn more.

Google-Extended

A robots.txt token that lets site owners control whether Google can use their content for its Gemini models. Google says it doesn’t affect inclusion in Google Search.

llms.txt

A proposed convention for a plain-text file that summarizes a site for large language models. It is an emerging idea; major engines haven’t confirmed that they use it.

Indexing

When a search engine stores a page so it can be shown in results. Pages generally need to be indexed before Ai search features can retrieve and cite them.

Featured snippet

A short answer Google shows at the top of some results, taken from one page and credited with a link. An early form of answer engine optimization.

Measurement

Buyer question set

A fixed list of the questions real buyers ask, from early research to “who should I hire”, used to test Ai engines consistently over time. Learn more.

Ai visibility score

A score summarizing how a business appears across a question set: for example, points for being recommended, mentioned or cited, divided by the points available. Learn more.

Share of voice

How often your business is named compared with the competitors who appear for the same questions.

Source gap

A site that Ai engines cite for your buyer questions where your business isn’t present, such as a directory, review site or “best of” list. Closing source gaps is often the fastest GEO win.