The glossary

One page per term, one plain definition per page, written for business owners rather than SEO professionals. Each definition is short on purpose: it is the sentence you can repeat in a meeting.

• 301 redirect

  A 301 redirect is a server instruction saying a page has moved permanently to a new address, so browsers and search engines are sent there and Google treats the new URL as the one to show in results.

• AEO (Answer Engine Optimisation)

  AEO is the practice of structuring content so answer engines, from Google AI Overviews to ChatGPT, can extract it as the direct answer to a question and cite you as the source.

• AI agent

  An AI agent is software that carries out a task on a person's behalf, such as comparing suppliers or filling in a form, by reading and acting on websites rather than only answering a question.

• AI Mode

  AI Mode is Google's conversational search experience, which decomposes one question into many parallel sub-queries (query fan-out) and composes an answer across them, rewarding sites that cover a topic thoroughly.

• AI Overviews

  AI Overviews are the AI-generated summaries Google shows above its classic results, composed from indexed pages and citing a handful of sources, which now absorb a large share of informational clicks.

• Core Web Vitals

  Core Web Vitals are Google's three field-measured user experience metrics: LCP for loading speed, INP for responsiveness to interaction, and CLS for visual stability.

• E-E-A-T

  E-E-A-T stands for Experience, Expertise, Authoritativeness and Trustworthiness: Google's framework for judging whether content deserves to be believed, increasingly mirrored by AI assistants choosing what to cite.

• Entity SEO

  Entity SEO is the practice of making search engines and AI assistants recognise you as one specific, unambiguous entity, so everything they learn about you attaches to the right record.

• GEO (Generative Engine Optimisation)

  GEO is the umbrella term for optimising a business's presence across generative AI search surfaces, covering both being cited as a source and being described and recommended accurately.

• Knowledge graph

  A knowledge graph is a machine's structured map of entities and the relationships between them, which search engines and AI systems consult to state facts rather than merely match keywords.

• LLM visibility

  LLM visibility is the degree to which AI assistants such as ChatGPT, Gemini, Claude and Perplexity know your business exists, describe it accurately, and recommend it when a buyer asks.

• llms.txt

  llms.txt is an optional plain-text file at the root of a website that gives AI models and agents a short summary of the site and links to its main pages; Google Search does not use it.

• Query fan-out

  Query fan-out is the way AI search breaks one question into several related searches that run at the same time, then builds a single answer from everything those searches return.

• sameAs

  sameAs is a structured data property that lists the URLs of other pages about the same company or person, such as its LinkedIn page or Wikidata entry, so search engines can tell which entity a website belongs to.

• Site migration

  A site migration is any change that moves a website's pages to new addresses, such as a rebuild on a new system, a new domain or a switch to HTTPS, and it needs planned redirects to keep search visibility.

• Structured data

  Structured data is machine-readable markup, usually JSON-LD using schema.org vocabulary, that states facts about a page and its entities explicitly instead of leaving machines to infer them from prose.