Glossary
JSON-LD
Definition
The format Google recommends for structured data: a small block of JSON inside a script tag in the page, describing the entities on it and their relationships without changing anything a visitor sees.
Its virtue is separation: the markup lives in one clean block rather than being woven through the visible HTML, which makes it easy to generate correctly, easy to validate, and easy for a crawler to extract. Every page on this site carries one; view source and it is the script block near the top.
The alternative formats, microdata and RDFa, still parse, but JSON-LD is where the tooling and the recommendations have settled. There is no reason to choose anything else for a new build.
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