JSON - Overview

JSON or JavaScript Object Notation is a lightweight text-based open standard designed for human-readable data interchange. Conventions used by JSON are known to programmers, which include C, C++, Java, Python, Perl, etc.

  • JSON stands for JavaScript Object Notation.

  • The format was specified by Douglas Crockford.

  • It was designed for human-readable data interchange.

  • It has been extended from the JavaScript scripting language.

  • The filename extension is .json.

  • JSON Internet Media type is application/json.

  • The Uniform Type Identifier is public.json.

Uses of JSON

  • It is used while writing JavaScript based applications that includes browser extensions and websites.

  • JSON format is used for serializing and transmitting structured data over network connection.

  • It is primarily used to transmit data between a server and web applications.

  • Web services and APIs use JSON format to provide public data.

  • It can be used with modern programming languages.

Characteristics of JSON

  • JSON is easy to read and write.
  • It is a lightweight text-based interchange format.
  • JSON is language independent.

Simple Example in JSON

The following example shows how to use JSON to store information related to books based on their topic and edition.

   "book": [
         "language": "Java",
         "edition": "third",
         "author": "Herbert Schildt"
         "language": "C++",
         "edition": "second",
         "author": "E.Balagurusamy"

After understanding the above program, we will try another example. Let's save the below code as json.htm

      <title>JSON example</title>
      <script language = "javascript" >
         var object1 = { "language" : "Java", "author"  : "herbert schildt" };
         document.write("<h1>JSON with JavaScript example</h1>");
         document.write("<h3>Language = " + object1.language+"</h3>");  
         document.write("<h3>Author = " + object1.author+"</h3>");   

         var object2 = { "language" : "C++", "author"  : "E-Balagurusamy" };
         document.write("<h3>Language = " + object2.language+"</h3>");  
         document.write("<h3>Author = " + object2.author+"</h3>");   
         document.write("<hr />");
         document.write(object2.language + " programming language can be studied " + "from book written by " + object2.author);
         document.write("<hr />");

Now let's try to open json.htm using IE or any other javascript enabled browser that produces the following result −

json example demo

You can refer to JSON Objects chapter for more information on JSON objects.