JavaScript Object Notation in short also known as JSON,is a lightweight data interchange format.JSON is easy for humans to read and write and easy for machines to parse and generate.These files are used
primarily to transmit data between a server and web application, as an alternative to XML.This format was originally specified by Douglas Crockford, and is described in RFC 4627 and ECMA-404.

The Internet media type for JSON is application/json.And the filename extension for JSON is .json. You can use a text editing application such as Notepad to open .json files.
A .json file script looks like this:
 
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