Free JSON Resources

JSON Tutorial
This is an introductory tutorial on JSON - JavaScript Object Notation at W3Resource. Includes examples of using PHP JSON functions to encode and decode information. It also includes examples of using JavaScript with JSON.

JSON Tutorial
The JSON Tutorial at tutorialspoint includes an overview and covers syntax, data types, objects, schema. It also includes short examples of encoding and decoding JSON data using PHP, Perl, Python, Ruby, Java and Ajax.

JSON: What It Is, How It Works, & How to Use It
Pretty much says it all.

JSON Processing (Java)
This is a section of the Java EE 7 tutorial which includes an introduction of JSON and focuses on JSON Processing in the Java EE Platform.

A JSON Tutorial. Getting started with JSON using JavaScript and jQuery
Includes examples that you can run on JSFiddle and see the results.

W3Schools JSON Tutorial
Covers the basics including creating JavaScript object with eval.

JSON in JavaScript
A short article on JSON and JavaScript with links to an open source JSON parser and JSON stringifier.