Structured data is markup added to web pages using Schema.org vocabulary (typically in JSON-LD format) that tells machines what a page is about in explicit, parseable terms. Instead of inferring that a page is about a product from its words, structured data declares the entity type, name, description, price, and relationships directly. For AI-ready websites, structured data is foundational: it is the layer that enables AI systems, answer engines, and LLMs to extract and cite content with confidence.

Also known as: schema markup, JSON-LD, Schema.org markup, semantic markup