How AI Search Engines Work: Retrieval, Synthesis, and Sources
Understand the practical path from a search question to an AI-generated answer, including retrieval, synthesis, citations, variance, and what teams can measure.
GEO and AI search guides
Free, step-by-step guides to getting your brand into ChatGPT, Gemini, Perplexity and Google AI Overviews. Learn how AI search works, how to measure AI visibility, and how to get cited.
- 19practical guides
- 4topics, from basics to reporting
- 76 minto read every guide
- Freeno sign-up needed
Which guide do you need?
Start from the question your team is asking.
- Why doesn’t ChatGPT mention our brand?Read: How to Rank in ChatGPT and Get Cited: An Evidence-Led Guide
- How do we measure AI visibility?Read: How to Measure AI Search Visibility: A Practical Framework
- Which competitors does AI recommend?Read: AI Search Competitor Analysis: Compare Answers, Evidence, and Next Actions
- Is GEO different from SEO?Read: GEO vs SEO: What Changes in AI Search Optimization?
- Do we need an llms.txt file?Read: What Is llms.txt? Format, Example, and Whether You Need One
Learn how AI search works
What GEO, AEO and AI search optimization mean, how they differ from SEO, and how AI tools choose which brands to name.
GEO vs SEO: What Changes in AI Search Optimization?
GEO and SEO serve related but different jobs. Learn how traditional search optimization and generative engine optimization fit together in one measurable workflow.
AEO vs SEO: What Changes When Search Gives an Answer
AEO vs SEO compared: what each one measures, where they overlap, and how to run both without duplicating work.
GEO vs AEO: How Generative and Answer Engine Optimization Work Together
GEO and AEO overlap, but the labels point to different measurement emphases. Use this practical comparison to connect AI answers, sources, SEO, and buyer intent.
LLM Optimization vs GEO: What Teams Can Actually Improve
LLM optimization and GEO overlap, but neither is a magic ranking switch. Use this practical framework to separate model behavior from the evidence a team can improve.
What Is llms.txt? Format, Example, and Whether You Need One
What llms.txt is, the exact file format, a working example, which AI systems say they use it, and how to create one in minutes.
Measure AI search visibility
Choose the questions to track, run an AI visibility audit, and see how you compare with competitors.
How to build an AI prompt portfolio
Turn real customer questions into a scoped, repeatable set of prompts for your AI visibility program.
How to Measure AI Search Visibility: A Practical Framework
Learn how to measure AI search visibility with a repeatable prompt set, answer-level metrics, competitor context, citation evidence, and a clear reporting workflow.
How to Track Brand Visibility in AI Search: A Working Checklist
Set up a practical AI search visibility program with buyer prompts, repeatable collection, competitor context, citations, and an evidence-led review cadence.
AI Visibility Audit: A Step-by-Step Method for Your Brand
Run an AI visibility audit with a fixed question set, saved answers, separate presence, accuracy and source checks, a site-readiness review, and one repeatable recheck.
AI Search Competitor Analysis: Compare Answers, Evidence, and Next Actions
Compare brands across the same AI buyer questions, retain answer and source evidence, separate Google rankings from AI responses, and turn repeated gaps into testable actions.
Get cited in AI answers
Find the sources AI trusts, close citation gaps, and write content that ChatGPT and Google AI Overviews can quote.
How to Rank in ChatGPT and Get Cited: An Evidence-Led Guide
Learn how to improve the chance that ChatGPT and other AI search systems cite your brand with clear entities, useful evidence, accessible pages, and repeatable monitoring.
AI Citation Gap Analysis: Find the Sources Behind Competitor Visibility
Use AI citation gap analysis to compare your brand with competitors, identify missing evidence, and prioritize pages or authority work without guessing at model rankings.
How to Optimize Content for AI Search Without Chasing Tricks
A practical AI search optimization workflow: fix access, answer the question directly, add verifiable evidence, connect sources, and validate what changes.
Run an AI visibility program
Turn the work into a monthly routine, report it clearly, and choose the right tools.
How to run an AI visibility program
Create a review cadence that connects recorded answers to owned investigations, content tasks, and clear reporting.
15 AI Visibility Tools for Agencies (2026): Best Fit by Workflow
Compare 15 AI visibility platforms for agencies on client workspaces, prompt scope, answer evidence, reporting, and plan limits.
What Is an AEO Tracker? How to Track Your Brand in AI Answers
What an AEO tracker measures, why a rank tracker cannot measure AI answers, and a six-point checklist for choosing one.
What Is an AI Marketing Agency? Services, Costs and How to Choose
The two kinds of AI marketing agency, what each one does, what they cost, and how to choose one for search and AI answers.
Best GEO and AEO Agencies in 2026: How to Compare Them
GEO and AEO agencies compared by type, published pricing and what to check before hiring one. Digraph publishes this list and is included in it.
Common questions
What is GEO?
GEO, or generative engine optimization, is the work of making your brand more likely to appear in answers from AI tools such as ChatGPT, Gemini, Perplexity and Google AI Overviews.
What is the difference between GEO and AEO?
They describe the same goal with different names. AEO, answer engine optimization, is the older term. GEO is more common when talking about generative AI tools. Both focus on being named and cited in answers.
Where should I start?
Start with how AI search engines work, then build a short list of customer questions and run a first AI visibility audit. The handbook puts these steps in order.
How do I get my brand cited by ChatGPT?
Make sure AI crawlers can read your site, publish clear pages that answer buyer questions directly, and earn mentions on the review and comparison sites that AI already cites. The guide on getting cited by ChatGPT walks through each step.
Find out what AI tells your customers about you.
- Know where you stand. Who AI names, and who it doesn’t.
- Know what to fix. A clear list, not a vague score.
- Know if it worked. Re-check after every change.