As we know, SOAP API works with XML, and REST API works with JSON data. But what is JSON data, what is it used for?

JSON, or JavaScript Object Notation, is a schema-less, text-based representation of structured data that is based on key-value pairs and ordered lists. Although JSON is derived from JavaScript, it is supported either natively or through libraries in most major programming languages. JSON is commonly, but not exclusively, used to exchange information between web clients and web servers.

If you’re writing software that communicates with a browser or native mobile application, you should use JSON as the data format. If you’re using NoSQL databases, you’re pretty much stuck with whatever the database gives you. In relational databases that support JSON as a type, a good rule of thumb is to use it as little as possible.

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