679 JSON (JavaScript Object Notation) is a lightweight format that is used for data interchanging. It is based on a subset of JavaScript language (the way objects are built in JavaScript). As stated in the MDN, some JavaScript is not JSON, and some JSON is not JavaScript. An example of where this is used is web services responses.
https://stackoverflow.com/questions/383692/what-is-json-and-what-is-it-used-for



