JSON Data Types

JSON (JavaScript Object Notation) supports a limited set of data types. Unlike JavaScript, it cannot directly store functions, dates, or undefined values.

• JSON is text-based; all data is transmitted as strings.
• JSON is language-independent, but its syntax comes from JavaScript.
• Use JSON.parse() to convert JSON strings into JavaScript objects.
• Use JSON.stringify() to convert JavaScript objects into JSON strings.

1. String

• A sequence of characters enclosed in double quotes ("").
• Strings must use double quotes in JSON; single quotes are invalid.
• Example:

"name": "John"

2. Number

• Numeric values: integers or floating-point numbers.
• No quotes around numbers.
• Examples:

"age": 30
"price": 19.99

3. Object

• An unordered collection of key/value pairs.
• Enclosed in curly braces {}.
• Keys must be strings (double quotes), values can be any JSON type.
• Example:

"address": {
  "street": "123 Main St",
  "city": "New York",
  "zip": 10001
}

4. Array

• An ordered list of values, enclosed in square brackets [].
• Values can be of any JSON type, including objects or arrays.
• Example:

"employees": [
  {"firstName": "John", "lastName": "Doe"},
  {"firstName": "Anna", "lastName": "Smith"},
  {"firstName": "Peter", "lastName": "Jones"}
]

5. Boolean

• Represents logical values: true or false (no quotes).
• Example:

"isActive": true"isAdmin": false

6. Null

• Represents an empty or unknown value.
• Always written as null (no quotes).
• Example:

"middleName": null