Schema.org
Schema.org is a shared vocabulary of structured-data types — Article, Product, Person, FAQPage, DefinedTerm — embedded as JSON-LD in HTML so search engines and AI answer engines can extract structured meaning from a page.
Schema.org launched in 2011 and by 2026 is the lingua franca for structured data on the web. Pages declare their types and properties via JSON-LD blocks in the HTML head. Search engines (Google, Bing) use schema for rich results and knowledge graph; AI answer engines use schema to extract entities and claims. The highest-leverage types in 2026: Article + speakable, FAQPage, DefinedTerm, ItemList, HowTo, Organization with founder + sameAs, BreadcrumbList. Validate with Google Rich Results Test and the Schema Markup Validator before shipping.
When to use schema.org
- Every public-indexable page.
- Glossary, FAQ, list, comparison, and product pages especially.
Common mistakes
- Stale dateModified — search engines down-rank dishonest freshness signals.
- Conflicting @id refs across schema entries — breaks entity graphs.
FAQ
What is schema.org?
Schema.org is a shared vocabulary of structured-data types — Article, Product, Person, FAQPage, DefinedTerm — embedded as JSON-LD in HTML so search engines and AI answer engines can extract structured meaning from a page.
When should I use schema.org?
Every public-indexable page. Glossary, FAQ, list, comparison, and product pages especially.
What are the most common mistakes with schema.org?
Stale dateModified — search engines down-rank dishonest freshness signals. Conflicting @id refs across schema entries — breaks entity graphs.
Related terms
- AI search engine — An AI search engine answers a user's query by retrieving relevant web sources and synthesising a cited answer with a language model — the category that includes Perplexity, ChatGPT Search, Claude with web, and Gemini AI Overviews.
- Retrieval-augmented generation (RAG) — Retrieval-augmented generation (RAG) injects relevant documents into the prompt at query time so the model answers from your data instead of its training memory.
Sources
Last updated: 2026-06-01. Raw markdown: https://promtable.com/glossary/schema-org.md.