Schema markup
Schema markup is structured data added to a web page using the schema.org vocabulary, encoded as JSON-LD, that explicitly tells search engines and large language models what entities, relationships, and facts the page describes.
Definition
Schema.org is a shared vocabulary developed by Google, Microsoft, Yahoo, and Yandex that defines hundreds of types — Organization, Person, SoftwareApplication, Article, Product, Recipe, Event — each with structured properties. Pages annotate themselves with this vocabulary so search engines can ingest the underlying meaning rather than guessing from prose.
Schema is typically delivered as JSON-LD (JavaScript Object Notation for Linked Data) inside a script tag. JSON-LD is preferred over microdata or RDFa because it lives in the document head, doesn't pollute the visible HTML, and is easy to validate.
For AI search and AI Overviews, schema markup is increasingly load-bearing. LLMs ingest structured data more reliably than prose, and well-marked-up pages are dramatically more likely to be cited in AI-generated answers than equivalent pages without schema.
Why it matters
Three correct schema types beat ten redundant ones. Schema markup is the single highest-leverage technical SEO investment for AI search visibility — every Supercurve customer who ships proper Organization + SoftwareApplication + FAQPage schema sees measurable AI mention share lift within 30 days.
A SaaS company adds SoftwareApplication schema with the full feature list, four-tier Offer array, and customer reviews. Within weeks, ChatGPT begins citing the company's homepage in answers about its category — because the LLM can now ingest the structured facts cleanly.
Related terms
See schema markup measured against your URL.
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