Search and SEO
What is Structured data?
Structured data is machine-readable markup describing what a page is about, usually written as JSON-LD using the Schema.org vocabulary. It does not directly improve rankings; it removes ambiguity, which is what makes rich results and accurate AI answers possible.
Also called: schema markup · JSON-LD · Schema.org
What it is actually for
Disambiguation. Prose has to be interpreted; structured data states. A graph that says who published this, what they sell, where they operate and what it costs saves a machine from inferring any of it — and inference is where mistakes about your business come from.
The mistake that makes it worthless
Islands. An Organization node and a Person node that never reference each other are two unrelated assertions. The same two joined by founder and worksFor describe a business with a human in it, which is the thing you meant to say.
Link nodes with @id references, in one @graph, and check that every reference resolves to a node that actually exists.
What risks a penalty
- Review or AggregateRating markup for reviews that are not visible on the page, or that you wrote yourself
- FAQPage markup for questions a user cannot see
- HowTo wrapped around a list of benefits rather than an ordered procedure
Where this is covered in depth
A definition can only go so far. Schema markup that does something, and the kind that risks a penalty covers this properly — 3 minutes, free, no email required.
Who wrote this
Anas Bin Masud builds e-commerce sites and does technical SEO for businesses in the UK, Canada and Pakistan. These definitions come from client work rather than from a content brief — where an entry describes a mistake, it is usually one found on a real site. More about how I work.