Structured data
Also called: Schema.org, JSON-LD
Machine-readable information, often JSON-LD using schema.org, that describes a page to search engines.
Definition
It powers rich search results like ratings, prices and breadcrumbs. Testers can validate it with Google's Rich Results Test.
In practice
A product page includes JSON-LD with its name, price and availability, so search results show '€89 · In stock'.