A schema describes the shape of data or entities: what fields exist, what types they have, and how records relate. It is useful when multiple systems — or machines reading a page — must interpret information the same way.
Whilst schemas promise order, in practice drift between docs, databases, and JSON-LD creates conflicting “truths.” For example, the site says one product name and markup still lists the old one. We often recommend one canonical schema story across pages and data, and treating JSON-LD as a published map of that story — not a separate marketing invent.