AI SEO Reference
AI SEO Glossary: 40+ Terms Defined
The complete reference for AI SEO terminology. Learn what GEO, AEO, LLMO, llms.txt, and other AI search optimization terms mean.
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Use Ctrl+F (or Cmd+F on Mac) to search for specific terms on this page. This glossary covers all major AI SEO terminology including GEO, AEO, LLMO, and technical terms.
Core Concepts
AI SEO
Artificial Intelligence Search Engine Optimization. The practice of optimizing online content and presence to appear in AI-generated search results from platforms like ChatGPT, Perplexity, Claude, Gemini, and Google AI Overviews. AI SEO focuses on being cited and recommended by AI systems rather than ranking in traditional search results.
GEO
Generative Engine Optimization. A term for optimizing content to appear in generative AI search engines that create synthesized answers rather than showing a list of links. GEO emphasizes content structure, authority signals, and AI-readable formats.
AEO
Answer Engine Optimization. The practice of optimizing content to appear as the answer when users ask questions to AI-powered answer engines like ChatGPT, Perplexity, or Google AI Overviews. AEO focuses on creating content that directly and authoritatively answers specific questions.
LLMO
Large Language Model Optimization. Optimizing content specifically for large language models (LLMs) like GPT-4, Claude, and Gemini. LLMO involves structuring content so LLMs can easily extract, understand, and cite information.
AI Visibility
A measure of how often and prominently a brand, business, or website appears in AI-generated recommendations and answers. High AI visibility means AI systems frequently cite or recommend you when users ask relevant questions.
Zero-Click Search
A search where the user gets their answer directly without clicking through to a website. AI search increases zero-click searches because AI provides synthesized answers. AI SEO aims to be the source AI cites.
Citation
When an AI system references or quotes your content in its response, often with a link. Being cited by AI is the goal of AI SEO, similar to how ranking was the goal of traditional SEO.
AI Visibility Score
A metric measuring how often a brand appears in AI-generated responses across platforms. Calculated by testing multiple relevant prompts across ChatGPT, Perplexity, and other AI systems.
Technical
llms.txt
A markdown file placed at your website's root directory (example.com/llms.txt) that serves as a curated reading list for AI crawlers. It tells AI systems which content is most important on your site, including descriptions of key pages and resources. The standard was proposed by Anthropic.
llms-full.txt
An extended version of llms.txt containing comprehensive information about a website, business, or organization. While llms.txt is concise, llms-full.txt can include detailed FAQs, complete service descriptions, and extensive structured information for AI systems.
AI Crawler
A web crawler (bot) operated by AI companies to index content for their AI systems. Major AI crawlers include GPTBot and ChatGPT-User (OpenAI), ClaudeBot and Claude-Web (Anthropic), PerplexityBot (Perplexity), and Google-Extended (Google).
GPTBot
OpenAI's web crawler that indexes content for ChatGPT and other OpenAI products. Allowing GPTBot in your robots.txt enables your content to be discovered and potentially cited by ChatGPT.
ClaudeBot
Anthropic's web crawler that indexes content for Claude AI. ClaudeBot also looks for llms.txt files to understand site structure and content priorities.
PerplexityBot
Perplexity AI's web crawler that indexes content for their answer engine. Perplexity is known for citing sources directly in responses, making PerplexityBot indexing particularly valuable for visibility.
Schema Markup
Structured data added to web pages using JSON-LD format that helps search engines and AI systems understand content. Key schema types for AI SEO include Organization, FAQ, HowTo, Article, Product, and LocalBusiness schemas.
JSON-LD
JavaScript Object Notation for Linked Data. The recommended format for implementing schema markup on websites. JSON-LD is placed in a script tag in the page's head or body and provides structured data that AI systems can easily parse.
Bing Indexing
The process of getting your website indexed by Microsoft Bing's search engine. Critical for AI SEO because ChatGPT uses Bing for real-time web search. Without Bing indexing, ChatGPT cannot find or recommend your content.
Bing Webmaster Tools
Microsoft's free platform for website owners to submit sites for Bing indexing, monitor performance, and troubleshoot issues. Essential for AI SEO because of Bing's role in ChatGPT search.
robots.txt
A text file at your website's root that tells web crawlers which pages they can or cannot access. For AI SEO, robots.txt should explicitly allow AI crawlers (GPTBot, ClaudeBot, PerplexityBot) while blocking sensitive directories.
User-Agent
An identifier that web crawlers send when accessing your site. AI crawler user-agents include GPTBot, ChatGPT-User, ClaudeBot, Claude-Web, PerplexityBot, and Google-Extended. These are specified in robots.txt rules.
Semantic HTML
Using HTML elements according to their meaning (h1 for main heading, article for content, nav for navigation) rather than just for appearance. Semantic HTML helps AI systems understand content structure and hierarchy.
Retrieval-Augmented Generation (RAG)
A technique where AI systems retrieve relevant documents before generating responses. RAG-based AI (like Perplexity) searches the web in real-time, making fresh, well-optimized content important for visibility.
Training Data
The content AI models learned from during their training period. AI systems like ChatGPT and Claude have knowledge cutoffs - information after their training date requires real-time search to access.
FAQ Schema
Structured data markup (FAQPage schema) that identifies question-and-answer content on a page. FAQ schema helps AI systems understand and extract Q&A pairs for inclusion in responses.
HowTo Schema
Structured data markup that identifies step-by-step instructional content. HowTo schema helps AI systems understand procedural content and include it in responses to 'how to' questions.
Organization Schema
Structured data that provides information about a business or organization including name, logo, contact information, and social profiles. Helps AI systems confidently identify and recommend businesses.
LocalBusiness Schema
Structured data for businesses with physical locations, including address, hours, and service area. Critical for local AI SEO to appear in location-based AI recommendations.
Strategy
Brand Mentions
References to a business or brand name across the web, even without hyperlinks. In AI SEO, brand mentions are more important than backlinks because AI systems use them as trust and authority signals. More mentions on authoritative platforms increase AI recommendation likelihood.
Entity Optimization
Building a clear, consistent identity for a brand or business across the web so AI systems can confidently identify and recommend it. Includes consistent NAP (Name, Address, Phone), brand messaging, and presence on knowledge bases.
Content Extraction
How AI systems pull specific snippets of information from web content to include in their responses. Optimizing for content extraction involves using clear structure, front-loading answers, and formatting content in easily quotable segments.
Front-Loading
A content writing technique where the answer to a question is placed in the first sentence or paragraph. Front-loading makes it easier for AI systems to extract and cite your content as a direct answer.
Citable Content
Content structured in a way that AI systems can easily quote or reference. Citable content includes clear statements of fact, specific data points, step-by-step instructions, and definitive answers to questions.
Knowledge Graph
A database of entities (people, places, things) and their relationships used by search engines and AI systems. Appearing in knowledge graphs (Google Knowledge Graph, Wikidata) increases AI visibility and recommendation likelihood.
E-E-A-T
Experience, Expertise, Authoritativeness, and Trustworthiness. Google's quality guidelines that also influence AI systems. Demonstrating E-E-A-T through author credentials, citations, and authoritative content improves AI recommendation chances.
Prompt Tracking
Monitoring specific questions or prompts in AI systems to track whether your brand appears in responses. AI SEO services track prompts like 'best [service] in [location]' to measure visibility over time.
Digital PR
Public relations activities focused on gaining online coverage and brand mentions. In AI SEO, digital PR builds brand mentions on authoritative sites that AI systems trust.
NAP Consistency
Name, Address, Phone number consistency across the web. Consistent NAP helps AI systems confidently identify a business as a single entity, improving recommendation accuracy.
Platforms
AI Overviews
Google's AI-generated summaries that appear at the top of search results, synthesizing information from multiple sources to answer user queries. Also known as SGE (Search Generative Experience) during testing.
ChatGPT Search
OpenAI's ChatGPT with real-time web search capabilities powered by Bing. When users ask current questions, ChatGPT searches the web and synthesizes answers from multiple sources.
Perplexity AI
An AI-powered answer engine that provides sourced answers to user questions. Perplexity is known for citing sources directly and showing which websites informed its responses, making it a key platform for AI SEO.
Frequently Asked Questions
What is the difference between GEO, AEO, and LLMO?
GEO (Generative Engine Optimization), AEO (Answer Engine Optimization), and LLMO (Large Language Model Optimization) all refer to optimizing content for AI search systems. They're essentially different names for the same practice - AI SEO. GEO emphasizes generative AI platforms, AEO focuses on answer engines, and LLMO specifically targets large language models. All aim to get your content cited by AI.
What is llms.txt and do I need one?
llms.txt is a markdown file placed at your website's root (yoursite.com/llms.txt) that tells AI crawlers which content is most important. It acts as a curated reading list for AI systems. Yes, you should create one - it's a low-effort, high-impact AI SEO tactic that helps AI systems understand and prioritize your content.
Why are brand mentions more important than backlinks for AI SEO?
AI systems use brand mentions as trust signals to determine which businesses to recommend. Unlike traditional SEO where backlinks pass 'link juice,' AI systems evaluate overall brand presence and reputation across the web. A mention on Reddit or an industry forum can influence AI recommendations even without a link.
What is AI visibility and how is it measured?
AI visibility measures how often your brand appears in AI-generated responses. It's measured by testing relevant prompts across AI platforms (ChatGPT, Perplexity, etc.) and tracking how often you're mentioned or cited. AI Clearbridge offers a free visibility checker at aiclearbridge.com/ai-visibility.
Which AI crawlers should I allow in robots.txt?
You should allow: GPTBot and ChatGPT-User (OpenAI), ClaudeBot and Claude-Web (Anthropic), PerplexityBot (Perplexity), Google-Extended and GoogleOther (Google), Applebot-Extended (Apple), and cohere-ai (Cohere). Block only sensitive directories like /api/ or /admin/.
What is content extraction in AI SEO?
Content extraction is how AI systems pull specific information from your content to include in their responses. Optimizing for extraction means structuring content with clear headings, front-loading answers, using lists and tables, and creating quotable statements that AI can easily cite.
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