Here: https://json-ld.org/ https://json-ld.org/ JSON-LD is JSON for Linking Data. When you're passing semantic web data around or maybe storing it temporarily

Here: https://json-ld.org/ https://json-ld.org/ JSON-LD is JSON for Linking Data. When you're passing semantic web data around or maybe storing it temporarily in a text file (rather than in a triple-store) one of the formats you can use is JSON-LD. So that covers when you use it; the next question is why you use it over one of the other interchange or at rest formats. And generally the answer to that is that you're using Javascript as your language and you hate XML :) Anyway, less facetiously here is the blurb from the website! “Linked Data empowers people that publish and use information on the Web. It is a way to create a network of standards-based, machine-readable data across Web sites. It allows an application to start at one piece of Linked Data, and follow embedded links to other pieces of Linked Data that are hosted on different sites across the Web.” “JSON-LD is a lightweight Linked Data format. It is easy for humans to read and write. It is based on the already successful JSON format and provides a way to help JSON data interoperate at Web-scale. JSON-LD is an ideal data format for programming environments, REST Web services, and unstructured databases such as CouchDB and MongoDB.”