JavaScript

June 1, 2023

JavaScript Data Types

1- primitive datatype


// String

const name1 = "John Deo"; 
// Defined variable name1 and initialized value "John Dev".

console.log(name1); 
// ("run from",name1 )      

// Number

const num1 = 7;  
// Defined variable num1 and initialized 7 in num1 
        
const num2 = 3.1415;
// Defined variable num2 and initialized 3.1415 in num2
      
const num3 = 89e5;
// Defined variable num3 and initialized 89e5 in num3 
       
console.log(num1, num2, num3); 
// ("run from", num1, num2, num3)

// Boolean

const data1 = true;
// Defined data1 variable and initialized boolean value true  
  
const data2 = false;
//Defined data2 variable and initialized boolean value false   

console.log(data1, data2);
 // ("run from", data1, data2)

// Undefined

let undefine;  
// Defined undefine variable and left as is uninitialzed 
// without any value

console.log(undefine);
// ("run from", undefine)   

// Null

const n = null;
// Defined n variable (special keyword denoting a null value)  

console.log(n); 
// ("run from", n) 

// Symbol

let id = Symbol("nehal"); 
// Symbols are unique and cannot be changed. In JavaScript 
// ES6 it was introduced as a new primitive data type.

console.log(id);

Output


John Deo
7 3.1415 8900000
true false
undefined
null
Symbol(nehal)
2- Object datatype



// Array

const animal = ["cat", "dog", "goat"];
//  Defined animal variable and initialized 3 Array value

console.log(animal[1]); 
// ("run from animal[1] than print is index value 2(dog)
// and array value(1));

// Object;

const student = {    
// Defined student variable 
  
  Name: "Anil Kumar", 
// Defined object name  

  class: 6,   
// Defined object class      
    
  Roll: 45, 
// Defined object Roll            
};
console.log(student); 
// ("run from", student than print all object value)  

// Date

let now = Date();
// Defined now variable and initialized date and 
// Define value any date month year       

//alert=(now);
// ("run from", shows current date/time)

console.log(now);       

Output


dog
{ Name: 'Anil Kumar', class: 6, Roll: 45 }
Thu Jun 15 2023 13:04:55 GMT+0530 (India Standard Time)

Tags:

by : Nehal Akhtar

Quick Summary:

Data Types of JavaScript