JSON
From DocForge
JSON (JavaScript Object Notation) is a lightweight computer data interchange format. It is a text-based, human-readable format for representing objects and other data structures and is mainly used to transmit such structured data over a network connection (in a process called serialization).
JSON finds its main application in AJAX web application programming, as a simple alternative to using XML for asynchronously transmitting structured information between client and server.
JSON is a subset of the object literal notation of JavaScript and is commonly used with that language. However the basic types and data structures of most other programming languages can also be represented in JSON, and the format can therefore be used to exchange structured data between programs written in different languages.
The following example shows the JSON representation of an object that describes a person. The object has string fields for first name and last name, contains an object representing the person's address, and contains a list of phone numbers (an array).
{ "firstName": "John", "lastName": "Smith", "address": { "streetAddress": "21 2nd Street", "city": "New York", "state": "NY", "postalCode": 10021 }, "phoneNumbers": [ "212 732-1234", "646 123-4567" ] }
The JSON "standard" requires that the data be encoded as UTF-8. If the web page using JSON is another character set, such as Latin-1, the JSON will still be transmitted to and from the web server in UTF-8. This can occasionally be a point of confusion for web applications written in other character sets. PHP, for example, does not use Unicode by default, and therefore requires encoding and decoding of JSON strings if the newer JSON-specific functions aren't used.
