Product structured data
The Schema.org Product schema enables marking up price, availability, brand, reviews, and identifiers (GTIN, MPN) for an item. Google uses it to display merchant rich snippets, free listings in Google Shopping, and image results across its search surfaces.
In practice
The minimum viable implementation requires name, image, description, and offers (price, priceCurrency, availability). Adding sku and gtin improves eligibility for organic Google Merchant Center surfaces. A common mistake is marking up a promotional price without setting priceValidUntil — Google disables the rich snippet as soon as it detects a discrepancy between the markup and the live page.