The AEO & GEO glossary

Answer Engine Optimization (AEO) is the practice of optimizing content so AI answer engines like ChatGPT, Perplexity and Google AI Overviews name and cite your brand when they answer a question in your category.

Generative Engine Optimization (GEO) is the practice of optimizing content to be surfaced and cited by generative AI engines — ChatGPT, Gemini, Perplexity and AI Overviews — when they generate answers.

AI search visibility is how often, and how prominently, AI answer engines name your brand when users ask questions in your category — the AI-era equivalent of search ranking.

Share of voice in AI search is the percentage of all brand mentions in AI answers for your category that belong to you — a measure of category dominance, not just presence.

Citation rate is how often an AI answer engine links to or attributes your content as a source when it generates an answer, as opposed to merely naming your brand.

A brand visibility score is a single 0–100 index that summarizes how present your brand is across AI answers for your category, blending mention frequency, position and share of voice.

SEO optimizes to rank in a list of search links; GEO (generative engine optimization) optimizes to be named and cited inside a single AI-generated answer. They share foundations but reward different things.

AEO and GEO describe the same discipline from two angles: AEO frames it around the answer the user receives, GEO around the generative engine that composes it. In practice teams use the terms interchangeably.

LLMO (large language model optimization) is optimizing your brand and content to be represented accurately and favorably by large language models — overlapping heavily with AEO and GEO.

Entity authority is how well-established and trusted your brand is as a recognized entity across the web — the signal answer engines rely on most when deciding which brands to name.

llms.txt is a proposed plain-text file at your site root that gives AI models a curated, machine-readable summary of your most important content — an AEO analogue to robots.txt and sitemap.xml.

Google AI Overviews are the AI-generated summaries shown above traditional results for many searches, synthesizing an answer from multiple sources and citing a handful of them.

Prompt tracking is monitoring how AI engines answer a fixed set of buyer-intent prompts over time, so you can measure your brand’s visibility, share of voice and citations as a trend rather than a one-off snapshot.

An answer engine is a system that responds to a query with a direct, synthesized answer instead of a list of links — ChatGPT, Perplexity, Google AI Overviews and Gemini are answer engines.

A zero-click search is one where the user gets their answer directly on the results page or in an AI answer and never clicks through to a website — increasingly the default in AI search.

AI brand accuracy is whether AI engines describe your brand correctly — right facts, products, positioning and claims — as opposed to hallucinating or repeating outdated information.