JSON-LD

Structured data, Google likes it a lot.

• https://developers.google.com/search/docs/guides/intro-structured-data
• https://search.google.com/structured-data/testing-tool
• http://schema.org/

In HTML

<script type="application/ld+json">
{
	"@context": "http://schema.org",
	"@type": ...,
}
</script>