JSON-LD extends JSON to include linking information. Here's how it could make JSON a top-tier player in hypermedia and the semantic web.

If you don't know yet, all parameters sent through Fetch API must be in JSON format (body item). You can do it by yourself or use mine approach along with database.php.

With an example then make use of the built-in FormData and Fetch APIs (no external packages) to implement step by step form that sends data as JSON to an API endpoint.