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Published ByBilly Reiner

Glossary

The Shopify SEO and AI shopping glossary

The Shopify SEO vocabulary doubled in size between 2024 and 2026 — Shopify Catalog, agentic commerce, Knowledge Base, llms.txt, GEO, AEO, INP. Most of these didn't exist in their current form three years ago9. This page defines the 14 that materially change how a Shopify store shows up. One sentence each, plain English, with a longer page for every one.

Below is the alphabetical index. Every term links to a longer page that includes the Shopify-specific install note: where the field lives in admin, which doc says so, and what to do when the default behaviour is wrong.

How to read this glossary

If you Googled a term ("what is GEO?", "what is Shopify Catalog?") and want a one-sentence answer before reading further, every entry below gives that on one line. Click through to the longer page for the install-level treatment.

Where a term has rebranded or evolved — INP replacing FID as a Core Web Vital8, GEO emerging as the umbrella discipline that contains AEO — both terms are listed and the longer page documents the change with dates. Where Shopify has its own term for something other platforms call by a different name (Shopify Catalog, Knowledge Base, robots.txt.liquid), the longer page links the Shopify Help Center doc that names the feature first3.

A · B · C

A–C covers AEO and agentic commerce on the AI-search side, plus the canonical tag Shopify auto-generates on every page.

Agentic commerce
Agentic commerce is the pattern in which an AI agent helps a shopper discover, compare, and purchase products inside the AI conversation itself, rather than directing the shopper to a storefront. Shopify's own definition, published April 2026.
Answer Engine Optimization
Answer Engine Optimization (AEO) is the practice of structuring content so AI answer engines — ChatGPT, Perplexity, Claude, Gemini, Google AI Overviews — extract and quote your page as the answer to a user's question.
Canonical tag
A canonical tag is the rel=canonical link element that tells search engines which URL is the preferred address for a piece of content when duplicates or near-duplicates exist. Shopify themes auto-generate canonicals on every page.

D · E · F · G · H

Duplicate content, Generative Engine Optimization, GTIN. Three Shopify-specific terms that get mis-defined on generic SEO blogs.

Duplicate content
Duplicate content is the same or near-identical content reachable at more than one URL. On Shopify, the classic case is products appearing at both /products/{handle} and /collections/{collection}/products/{handle}.
Generative Engine Optimization
Generative Engine Optimization (GEO) is the broader discipline of getting cited inside generative-AI responses across every engine — Answer Engine Optimization plus retrieval-graph, entity, and citation-hygiene work.
GTIN
GTIN (Global Trade Item Number) is the GS1 standard product identifier — UPC, EAN, ISBN, and JAN are all GTINs. Shopify exposes it through the product Barcode field.

I · J · K · L

INP, JSON-LD, Knowledge Base, LCP, llms.txt. I–L holds the install-critical concepts: Core Web Vitals, the schema syntax Google prefers, the FAQ app AI agents read, and Jeremy Howard's publisher manifest.

Interaction to Next Paint
Interaction to Next Paint (INP) is the latency between a user interaction (click, tap, key) and the next paint. INP replaced First Input Delay as a Core Web Vital on 12 March 2024. The 'good' threshold is 200 ms or less.
JSON-LD
JSON-LD is the JSON-based syntax Google recommends for emitting Schema.org structured data, written inside a <script type="application/ld+json"> tag in the page's HTML.
Knowledge Base app
Shopify Knowledge Base is a free first-party app that exposes the FAQs AI shopping agents use to answer questions about a store. Launched 16 May 2025; English only at launch.
Largest Contentful Paint
Largest Contentful Paint (LCP) is the time from page navigation to the render of the largest visible image, text block, or video. The Core Web Vital threshold for 'good' is 2.5 seconds or less.
llms.txt
llms.txt is a proposed plain-text manifest at the root of a site (e.g. example.com/llms.txt) that lists the URLs an LLM should prefer when answering questions about the site. Proposed by Jeremy Howard, September 2024.

M through Z

robots.txt.liquid, Shopify Catalog, structured data. M–Z holds the Shopify-native files and types — the file that controls how crawlers see the store, the feed AI channels read, and the schema layer themes auto-emit.

robots.txt.liquid
robots.txt.liquid is the Shopify theme template that renders the store's /robots.txt file. It is the only way to customise robots rules on a Shopify store, and Shopify Support warns it can take down all traffic if edited incorrectly.
Shopify Catalog
Shopify Catalog is a comprehensive global catalog of eligible products that are sold by stores on Shopify. AI channels — ChatGPT, Copilot, Gemini, Perplexity, Shop — read Catalog data to power discovery, ranking, and recommendations.
Structured data
Structured data is machine-readable markup that describes the meaning of page content (a product, a person, an article) in a standard vocabulary like Schema.org. Shopify themes auto-emit Product schema.

Where each term lives in the rest of the site

A glossary entry is rarely the whole answer. Below is the routing map: where each cluster of terms goes for the install-level treatment. The 14 deep pages cover the long-form definition; the pillars cover the install; the FAQ hub covers the question-shaped variant.

The newer the term, the more Shopify-specific the install. Older mechanics like the canonical tag and structured data are about the same across every platform; the 2024–2026 vocabulary each requires an explicit Shopify-side step (Catalog needs plan + product eligibility, llms.txt has no native Shopify support, INP needs theme-level interaction tuning). The longer pages spend more time on the AI-era terms because that's where the platform-specific work lives.

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