Reference

AI search reference

Definitions of the terms used across this publication. Each reference page opens with a standalone answer, lists what is documented against what is inferred, and links to the research that uses the concept.

Reference pages

ai-search

AI search optimisation

AI search optimisation is the work of making a source usable by AI-assisted search: systems that retrieve documents at answer time, compose a response with a language model, and attach citations to some of what they used. It differs from optimising for a ranked list because the unit is the retrieved passage and the outcome is being composed from and cited, not a position. What the platforms document is access and eligibility; how they select among eligible sources is largely undisclosed.
ai-seo

AI SEO

AI SEO is the practice of making a business visible to AI-assisted search: systems such as ChatGPT, Google AI Overviews, Gemini and Perplexity that retrieve sources and compose an answer rather than listing links. It covers whether those systems can reach a site, identify the business, retrieve the right passage and cite or recommend it. In Perth, Western Australia, that means being one of the sources an assistant draws on when someone asks a Perth question.
ai-seo

AI SEO vs SEO

AI SEO extends SEO rather than replacing it. On Google, the relationship is documented: existing SEO best practices remain relevant for AI Overviews and AI Mode, with no additional requirements. What carries over is technical accessibility, indexing, useful content and clean structure. What is new is the unit of optimisation (the passage rather than the page), the need for the business to resolve as one entity, prompt coverage instead of keyword lists, corroboration instead of link authority, and measurement by repeated sampling instead of rank tracking.
aeo

Answer Engine Optimisation

Answer Engine Optimisation (AEO) is the practice of structuring content so a search system can extract it as the direct answer to a question. It predates generative AI: featured snippets, voice assistants and knowledge panels were the original answer engines. AI Overviews, AI Mode and chat assistants extend the same demand for passages that answer a question plainly, near the top, in a form that stands on its own when lifted from the page.
chatgpt

ChatGPT SEO

ChatGPT SEO is the work of making a business reachable and usable by ChatGPT when it searches the web to answer a question. OpenAI documents three agents: GPTBot gathers training data, OAI-SearchBot indexes sites for ChatGPT's search features, and ChatGPT-User fetches pages when a user asks. Sites that opt out of OAI-SearchBot are not shown in ChatGPT search answers. How ChatGPT ranks the sources it retrieves is not documented.
entities

Entity SEO

Entity SEO is the practice of making a business identifiable as one distinct entity, rather than a string of words, across the sources search engines and AI-assisted search systems read: one canonical name, one consistent set of facts, explicit relationships between the organisation, its people, services and locations, and agreement between the business's own site, registries, directories and profiles. A system that cannot resolve a business to one entity cannot confidently name it in an answer.
gemini

Gemini SEO

Gemini SEO is the work of being reachable by, and usable in, answers from Google's Gemini app. Google documents that some Gemini responses are grounded on Google Search results, and that the Google-Extended robots.txt token controls whether crawled content may be used to train Gemini models and to ground Gemini answers, without affecting inclusion or ranking in Google Search. Gemini is a separate surface from AI Overviews and AI Mode and is recorded separately in this publication's research.
geo

Generative Engine Optimisation

Generative Engine Optimisation (GEO) is the practice of improving how visible a source is in the answers composed by generative engines, the search systems that use a large language model to synthesise a response with citations. The term was introduced in a 2023 research paper that tested content changes against a benchmark of queries. In practice GEO overlaps almost entirely with AI SEO; the difference is origin and emphasis, not mechanism.
google

Google AI Overviews

Google AI Overviews are generative summaries shown at the top of some Google Search results, with links to supporting pages. Google states they are a core Search feature drawn from the normal Search index: a page must be indexed and eligible for a snippet to be a supporting link, there are no additional requirements, and no special markup is needed. AI Overviews are available in Australia, so they appear for Perth searches.
perplexity

Perplexity SEO

Perplexity SEO is the work of being reachable by, and cited in, Perplexity's answers. Perplexity documents two agents: PerplexityBot, which surfaces and links websites in its search results, and Perplexity-User, which visits a page when a user asks a question and includes a link to it in the response. Perplexity states neither collects content for training foundation models. Because Perplexity shows citations by default, it is the surface where source patterns can be observed most completely.

Glossary

Short definitions for terms that recur in the methodology and reports but do not need a page of their own.

AI-assisted search: Any search experience where a generative model composes the answer, with or without citations, instead of returning only a ranked list of links.
Citation: A link or source reference an AI answer attaches to a statement. Citation display differs by platform and is not always shown.
Mention: A business or brand named anywhere in an AI answer, whether or not it was recommended.
Recommendation: A business or brand an AI answer presents as a shortlist entry or suggested option.
Retrieval: The step where a system fetches documents or facts to ground an answer, as distinct from what the model learned in training.
Grounding: Tying an answer to retrieved sources so the response reflects current documents rather than only training data.
Query fan-out: Google's term for issuing several related searches from one prompt and combining what comes back. Documented by Google for AI Mode.
Source class: The category of a cited domain in this publication's methodology: owned, third-party, platform-owned, UGC, directory, publisher or brand source.
Session variance: The difference between answers to the same prompt across repeated runs, sessions or accounts.
Prompt set: The fixed list of prompts a study runs, kept constant so repeated rounds are comparable.
Entity: A distinct thing (a business, person, place or product) that a system can identify and attach facts to, as opposed to a keyword string.
Knowledge graph: A database of entities and the relationships between them. Google's Knowledge Graph feeds Knowledge Panels and entity understanding in Search.