Data Types in JavaScript

INTRODUCTION

  Data Types in JavaScript

JavaScript Data Types

        
            JavaScript has two main types of data: 
            Primitive and 
            Non-Primitive (Reference) types.
        

        
        1. Primitive Data Types
        These types store a single value and are immutable.

        
            a) String
            A sequence of characters enclosed in quotes.
            let name = "John Doe";
console.log(typeof name); // Output: string
            
        

        
            b) Number
            Represents both integer and floating-point numbers.
            let age = 25;
console.log(typeof age); // Output: number
            
        

        
            c) Boolean
            Represents true or false values.
            let isLoggedIn = true;
console.log(typeof isLoggedIn); // Output: boolean
            
        

        
            d) Undefined
            A variable that has been declared but not assigned a value.
            let x;
console.log(typeof x); // Output: undefined
            
        

        
            e) Null
            Represents an intentional absence of value.
            let y = null;
console.log(typeof y); // Output: object (JavaScript quirk)
            
        

        
            f) Symbol (ES6)
            Used for unique identifiers.
            let sym = Symbol("unique");
console.log(typeof sym); // Output: symbol
            
        

        
            g) BigInt (ES11)
            Used for very large numbers.
            let bigNumber = 9007199254740991n;
console.log(typeof bigNumber); // Output: bigint
            
        

        
        2. Non-Primitive (Reference) Data Types
        These types store references to memory locations.

        
            a) Object
            Used to store key-value pairs.
            let person = { name: "Alice", age: 30 };
console.log(typeof person); // Output: object
            
        

        
            b) Array
            A collection of values in a single variable.
            let fruits = ["Apple", "Banana", "Cherry"];
console.log(typeof fruits); // Output: object
            
        

        
            c) Function
            A reusable block of code.
            function greet() {
    return "Hello!";
}
console.log(typeof greet); // Output: function
            
        

        
            d) Date
            Represents date and time.
            let today = new Date();
console.log(typeof today); // Output: object
            
        

        Conclusion
        
            JavaScript has **7 primitive** and **several non-primitive** data types. 
            Primitive types store values directly, while non-primitive types store references.