Answers for "differenfce between let & const javascript"

difference between let, var and const in java script

//let is used to declare the variable or initialize a variable..
//let variable can be updated in future.
//Its block scope and we cannot redeclare it.

let a; // Initializing the variable.
let b = 4; // Initializing and declaring variable.
let b = 5; //Error:- cannot redeclare a value but we can update the value.

//var is just like let but var is used to declare a variable value at top of
//the program, its hoisted.

var a; // Initializing the variable.
var b = 4; // Initializing and declaring variable.
var b = 5; //b will be redeclared and we can update its value.

//const variable should be declared and intialized at same time.
//const variable cannot be updated in future.
//we cannot even redeclare the variable in future.

const a = 10; //Initilizing and declaring a variable at a time.
const b; //Error:- const should be declared and intialized.
const a = 11 // Error:- cannot redeclare the variable again.

difference in var let and const

var: 
	* hoisted(global scope)
    * function scope
let:
    * block scope
    * reassignable
    * not redeclarable
const: 
    * block scope
    * not reassignable
    * not redeclarable