Product (schema.org)
The schema.org type Product makes product details such as name, description, image, price, availability and ratings machine-readable for search engines and thereby enables richer presentation in the search results.
In practice
In e-commerce, Product is the standard type for item pages and can be combined with Offer for price and availability and with AggregateRating for ratings. Service providers can use Product too, for example for physical goods connected with their offering. It is important that all marked-up values match the details visible on the page exactly, because Google penalises discrepancies.