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JavaScript Variable
Variable are used to storing data in single variable
JavaScript variable create three type
1- Using var keyword
2- Using let keyword
3-Using const keyword
Use var keyword - Generally var keyword indicate a variable which store data
Note : You can redeclare var keyword variable
Note : You can reassign var keyword variable
Example
/**********This is index.js file************/
var x = "Hello Word";
// You can print this variable
console.log(x);
var int = 1245751;
console.log(int);
Result
Hello Word
1245751
JavaScript Redeclare Variable
var int = 52;
console.log(int);
var int =16;
console.log(int);
Result
52
16
JavaScript Reassign Variable
You can reassign variable by this method
var int = 48;
console.log(int);
int = 26; //without using var keyword
console.log(int);
Result
48
26
JavaScript Let Keyword
You can reassign variable but can not redeclare variable in let keyword
Example
let int = 12;
console.log(int);
int = 16; // We reassign value int vaiable
console.log(int);
Result
12
16
JavaScript Const Keyword
You can not reassign and redeclare variable in const keyword variable
Example
cont int = 42.5;
console.log(int);
// you can not reassign and redeclare in const keyword variable
//if you you try to reassign and redeclare it give error
/* * const int = 45;
console.log(int); **/
/** int =46;
console.log(int); **/
// It also give an error