Search visibility is how easily people find your business when they look for information, whether in Google results, maps, featured answers or AI assistants such as ChatGPT and Gemini. Learning a small set of terms makes the subject much easier: crawling, indexing and ranking explain how search engines work; snippets and answer boxes explain AEO; citations, entities and AI crawlers explain GEO. This glossary defines the most useful terms in plain English, then suggests an order to learn them in.
How search engines work: core terms
- Crawling: the process by which search engine bots, such as Googlebot, discover pages by following links and reading sitemaps.
- Indexing: storing and understanding a crawled page so it can be shown in results. A page that is not indexed cannot rank.
- Ranking: the order in which indexed pages are shown for a search, based on relevance, quality, usability and trust.
- SERP: the search engine results page, which can include organic results, ads, maps, images, videos and AI-generated summaries.
- Search intent: what the searcher actually wants, such as information, a comparison, a specific website or a purchase.
- Organic results: unpaid listings that appear because a search engine judged them relevant.
Technical SEO terms
- robots.txt: a file that tells crawlers which parts of a site they may or may not crawl.
- XML sitemap: a list of a site’s important URLs that helps search engines discover them.
- Canonical tag: a signal telling search engines which version of similar or duplicate pages is the main one.
- Noindex: an instruction asking search engines not to show a page in results.
- 301 redirect: a permanent redirect from an old URL to a new one, passing visitors and signals along.
- Core Web Vitals: Google’s metrics for loading speed, responsiveness and visual stability.
- Structured data (schema): code that describes page content, such as a business, product or article, in a format machines can read.
Content and authority terms
- Keyword: a word or phrase people type or speak into a search engine.
- Topic cluster: a main page on a broad subject linked to supporting pages that each answer a specific question.
- Internal link: a link from one page on your site to another, helping visitors and search engines navigate.
- Backlink: a link from another website to yours, which can signal trust when it comes from a relevant, reputable source.
- E-E-A-T: experience, expertise, authoritativeness and trustworthiness, the qualities Google’s quality rater guidelines use to describe reliable content.
- Local SEO: improving visibility for searches with a location, including Google Maps and the local pack.
Answer engine (AEO) terms
- Answer engine: any system that responds with a direct answer rather than only a list of links, including search features and voice assistants.
- Featured snippet: a highlighted excerpt from a web page shown near the top of Google results to answer a question.
- People also ask: an expandable box of related questions and short answers in Google results.
- Zero-click search: a search where the user gets the answer on the results page and does not click any result.
- Voice search: spoken queries to assistants and smart devices, which usually return one answer.
Generative engine (GEO) and AI search terms
- Generative engine: an AI system that writes answers by combining information from many sources, such as ChatGPT, Gemini, Perplexity, Copilot and Claude.
- AI Overview and AI Mode: Google’s AI-generated summaries and conversational search experience, which link to supporting web pages.
- Citation: a source an AI answer links to or names as the basis for its response.
- Entity: a clearly identifiable thing, such as a business, person or place, that search engines and AI systems can recognise and connect facts to.
- AI crawler: a bot run by an AI company, such as OpenAI’s OAI-SearchBot for ChatGPT search or GPTBot for model training.
- Grounding: when an AI system bases its answer on retrieved, current sources rather than only on what it learned in training.
- Hallucination: an AI answer that states something false with confidence, often caused by missing or conflicting information.
A suggested learning path
- Start with SEO: crawling, indexing, ranking and search intent are the foundation for everything else.
- Move to AEO: how to structure content so it can be quoted as a direct answer.
- Finish with GEO: how AI assistants find, describe and cite businesses.
- Compare the three side by side in SEO vs AEO vs GEO.
When you are ready to act, the step-by-step plan to improve AI visibility turns these concepts into tasks.