What is JSON? A Complete Guide

JSON (JavaScript Object Notation) is a lightweight data interchange format that's easy for humans to read and write, and easy for machines to parse and generate. Despite its name, JSON is language-independent and is used across virtually all programming languages.

JSON Syntax Basics

JSON is built on two structures:

• Objects: A collection of key-value pairs enclosed in curly braces {}
• Arrays: An ordered list of values enclosed in square brackets []

Example JSON Object

{
  "name": "John Doe",
  "age": 30,
  "email": "john@example.com",
  "isActive": true,
  "address": {
    "city": "New York",
    "country": "USA"
  },
  "hobbies": ["reading", "coding", "gaming"]
}

JSON Data Types

JSON supports the following data types:

• String: Text enclosed in double quotes
• Number: Integer or floating-point
• Boolean: true or false
• Null: Empty value represented as null
• Object: Key-value pairs
• Array: Ordered list of values

Common Use Cases

JSON is widely used for:

• API responses and requests
• Configuration files
• Data storage
• Cross-platform data exchange

JSON Best Practices

• Always use double quotes for strings and keys
• Don't include trailing commas
• Use meaningful key names
• Keep nesting levels reasonable
• Validate JSON before processing