Variable & Function hoisting in javascript

-
Hoisting is JavaScript's default behavior of moving declarations to the top of the current scope.

 Hoisting can be applied to variable declarations and to function declarations. As a result of this, JavaScript functions & variables can be called before they are declared.

 For example : - 

 1. variable Hoisting : 
x = 8; 
console.log(x); // prints  8

var x;

2. Function Hositing : - 
displayName();

function displayName () {
     console.log("I am rroxy");
}
* Function Hoisting applies to only functions not functions expressions, e.g : -
displayName(); // undefined

var displayName = function () {


console.log("I am rroxy");


}

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