JSON is a useful data serialization and messaging format. This specification defines JSON-LD 1.1, a JSON-based format to serialize Linked Data. The syntax is designed to easily integrate into deployed systems that already use JSON, and provides a smooth upgrade path from JSON to JSON-LD. It is primarily intended to be a way to use Linked Data in Web-based programming environments, to build interoperable Web services, and to store Linked Data in JSON-based storage engines. This specification describes a superset of the features defined in JSON-LD 1.0 [https://www.w3.org/TR/json-ld/#bib-json-ld10] and, except where noted, documents created using the 1.0 version of this specification remain compatible with JSON-LD 1.1.