What structured data actually does for a model
Structured data is markup added to a page that a visitor never sees and a machine reads directly — a way of stating who or what a page is about in a form built for parsing rather than persuading. It does not make a page more convincing to a person, and by Google's own account it does not directly improve where a page ranks either. What it removes is the guesswork a machine would otherwise have to do to work out what an ordinary paragraph is actually claiming — and guesswork is exactly what an assistant, working from a page it retrieved rather than a person reading it slowly, has the least room to do.
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