JSON is a simple way of representing data. A simple format that can be exchanged easily between machines and can be even understood by humans.
JSON, which stands for “JavaScript Object Notation”, is a lightweight computer data interchange format. JSON is a subset of the object literal notation of JavaScript but its use does not require JavaScript.
JSON’s simplicity has resulted in its widespread use, especially as an alternative to XML in Ajax. One of the claimed advantages of JSON over XML as a data interchange format in this context is that it is much easier to write a JSON parser. In Javascript itself, JSON can be parsed trivially using the eval() procedure. This was important for the acceptance of JSON within the AJAX programming community because of JavaScript’s ubiquity among web browsers.
JSON parsers are available for almost all popular languages. JSON is very similar to how we have been passing around data using JavaScript and ActionScript. It’s simpler than PHP’s serialization routines and works pretty well.
You can learn more about JSON from the official JSON site. Yahoo! is very hot about JSON and Google too uses it well. JSON is widely know as the “fat free alternative to XML” 🙂