Introduction to JSON

This article is about the basics of JavaScript Object Notation (JSON). The following describes JSON:
  • lightweight text data interchange format
  • language-independent
  • easy to understand
  • self-describing
JSON is nothing but a lightweight text data interchange format, that is widely used for describing data. It is easily converted to most programming languages for use in many APIs such as:
  • Flicker
  • Twitter
  • Instagram
  • Photobucket
  • Google Geocoder
  • Tumblr
  • Yahoo Travel
  • Yahoo Answers
  • Yelp
And so on, now offers their result in this format.
It’s a way of annotating data that’s relatively easy for programmers to perform operations like read and write. This helps explain the current context of the use of JSON. It works similarly to Asynchronous JavaScript and XML (AJAX), which generally depends upon the concepts of JavaScript.
Programmers have searched for an easy way to transfer data. Converting JSON to something usable in JavaScript takes one line of code and automatically works in all types of web browsers.

JSON Objects

Creation of objects in JSON is done between a pair of curly brackets. Objects in JSON can have multiple values in this scenario too.
Single pair value in JSON
{ “firstname”:“abhishek” , “lastname”:”jaiswal”},
Multiple pair value in JSON
{ “firstname”:“abhishek” , “lastname”:”jaiswal”},
{ “firstname”:“a1” , “lastname”:”j1”},
{ “firstname”:“a2” , “lastname”:”j2”},
{ “firstname”:“a3” , “lastname”:”j3”},

JSON Array

Just as in other programming languages JSON also uses square [] brackets for representing an array.
Moreover, an array can have multiple objects.
{“student”:[{ “firstname”:“abhishek” , “lastname”:”jaiswal”},
{ “firstname”:“a1” , “lastname”:”j1”},
{ “firstname”:“a2” , “lastname”:”j2”},
{ “firstname”:“a3” , “lastname”:”j3”},]}
The preceding example shows the basic structure of the JSON.


There are several technologies like JSON, one of the most famous and used among those languages is XML. But there are several differences that create hurdles between JSON and XML. These hurdles provide these functionalities to JSON, which are not present in XML. Some of these features of JSON are as follows:
  • There are no ending Tags in JSON.
  • No reverse word concept in JSON
  • JSON uses the functionality of ARRAYS
  • Ease of read and write operations
  • Easily works with JavaScript
  • can be used in enhancing functionalities of AJAX
  • is shorter
  • can be parsed using JavaScript
  • JSON performs read and write operations much more easily than XML
  • JSON can be used in AJAX apps in place of XML
  • JSON works more effectively than XML
  • Enhanced features than XML

JSON Parser

For parsing in JSON we use the eval() function. This function can compile and execute any JavaScript code. It is comparatively safer to use the JSON parser to convert a JSON text to a JavaScript object. A JSON parser will recognize only JSON text written in the code and it's not going to compile script at all.
Some other features of JSON parser are
  • It is faster
  • It's more convenient
  • Reduces complexities
Referenced Example
  1. <html>    
  2. <head>    
  3.     <title>Record</title>    
  4. </head>    
  5. <body>    
  6.     <h1>Basics of JSON </h1>    
  7.     <p>    
  8.         Name <span id="”jName”"></span>    
  9.         <br />    
  10.         Roll_No <span id="”jRoll_No”"></span>    
  11.         <br />    
  12.         ID <span id="”jID”"></span>    
  13.         <br />    
  14.         DOB <span id="”jDOB”"></span>    
  15.         <br />    
  16.     </p>    
  17.     <script>    
  18.         var JSONobject= {    
  19.             “Name” : “abhishek”,    
  20.             “Roll_No” : 123,    
  21.             “ID” : “CSE”,    
  22.             “DOB” : “JAN 01”,    
  23.             );    
  24.         document.getElementById    
  25.         (“jName”)inner.HTML=JSONobject.Name    
  27.         document.getElementById    
  28.         (“jRoll_No”)inner.HTML=JSONobject. jRoll_No    
  30.         document.getElementById    
  31.         (“jID”)inner.HTML=JSONobject.ID    
  33.         document.getElementById    
  34.         (“jDOB”)inner.HTML=JSONobject.DOB    
  35.     </script>    
  36. </body>    
  37. </html>