Structured Data
Also called: Schema markup, JSON-LD
Structured data is machine-readable markup embedded in a page that states explicitly what its content means, most commonly using schema.org vocabulary in JSON-LD format.
Without it, a machine must infer from prose that a page describes a business, a product or an event. With it, the page says so directly: this is an Organization, this is its name, this is where it operates, these are its profiles elsewhere.
For answer engines the value is disambiguation. Structured data removes the guesswork about what an entity is and how it relates to others, which is precisely the guesswork that causes a business to be skipped.
Why it matters
It is the cheapest available intervention with the most reliable effect. Most sites either omit it or implement a fragment, which makes complete, accurate markup a genuine differentiator.
An example
A plumbing company's homepage says "serving Greater Manchester since 2009" in a paragraph. With structured data it also states, in a form no machine has to interpret: this is a Plumber, founded in 2009, serving Greater Manchester, at this address, with these opening hours, and the same company as these three directory profiles.
Common mistakes
- Marking up content that does not appear on the page. Markup must describe what a visitor can see.
- Adding a fragment and stopping. An Organization block with only a name tells an engine almost nothing.
- Using several disconnected blocks with no @id linking them, so the relationships between them are never stated.
Questions
- Is JSON-LD better than microdata?
- JSON-LD is what Google recommends and what most sites use, because it sits in one script block rather than being woven through the HTML. That makes it far easier to maintain and less likely to break when a template changes.
- Does structured data improve rankings?
- Not directly. It makes a page eligible for some rich results and removes ambiguity about what the page describes. For answer engines the benefit is being understood correctly, which is a precondition for being recommended.