The library that AI engines quote.

AI Search Optimization (AISO) is the practice of engineering brand visibility inside ChatGPT, Perplexity, Gemini, Claude, and Google AI Overviews · combining entity SEO, structured data, citation networks, and AI-readable content.

Entity SEO is the practice of defining your brand as a real, disambiguated entity across Schema.org, the Knowledge Graph, Wikidata, and authoritative citation networks · the foundation of every AI engine ranking.

Knowledge Graph Optimization earns a Google Knowledge Panel through Organization and Person schema, sameAs networks, Wikidata entries, and authoritative citations · the strongest signal in AI search.

Answer Engine Optimization (AEO) targets featured snippets, AI Overviews, and direct answers. SEO targets ranked results. Modern brands need both because the same content fuels both surfaces.

Generative Engine Optimization (GEO) earns brand citations inside LLM-generated answers across ChatGPT, Perplexity, Gemini, and Claude · the discipline that defines visibility in 2026 search.

E-E-A-T (Experience, Expertise, Authoritativeness, Trustworthiness) is Google's quality framework and the dominant trust signal across AI answer engines · the foundation of citation eligibility.

Google AI Overviews use Gemini to summarize 3 to 6 sources at the top of the SERP. Cited sources are selected by classic ranking signals, Schema.org coverage, FAQPage markup, and AI-readable content blocks.

ChatGPT search blends OpenAI's retrieval layer with GPT-5 reasoning. Brands earn citations by combining classic SEO authority with entity SEO, FAQ schema, sameAs links, and dense AI-quotable content blocks.

Perplexity ranks brands through depth, recency, and sourced citations. Long-form content with dated lastUpdated, embedded citations, FAQ blocks, and entity SEO becomes the quoted answer.

Google Gemini draws from the Knowledge Graph, Google Search index, and Schema.org structured data. Brands earn Gemini citations through sameAs links, Knowledge Panel presence, and AI Overviews-ready content.

Schema.org structured data is the most under-deployed AI search signal of 2026. Organization, Person, Service, FAQPage, HowTo, LocalBusiness, BreadcrumbList, and Speakable schema fuel both classic and AI rankings.

llms.txt is a markdown file at the root of a website that summarizes brand, pages, and capabilities for AI crawlers and LLM training pipelines · the new robots.txt for AI search.