Javascript: Scope

SCOPE (Visibility, Accessibility)

every file is denoted as a module in js. "use strict" use strict is also scope strict mode on. With strict mode, you can not, for example, use undeclared variables. global scope can be used everywhere
var welcome = 'Welcome to home'; 

Example:

If you ask the phone store employee for a phone model that her store doesn't carry, she will not be able to sell you the phone you want. She only has access to the phones in her store's inventory. You'll have to try another store to see if you can find the phone you're looking for.

scope type: 

1. Global scope
2. local scope
3. functional scope
4. block scope

The scope is known as lexical scope. Each function has its own scope.
function hi(name){  

//hi is also global scope, accessible in every file

xyz = 'I am global scope';  

//global scope if not declared with var if there is use strict, then it can not be declared

var abc = hello('I am local scope');  

//abc is not global scope, its functional scope also known as local scope
console.log('abc', abc);
return 'Hello ' + name + ' ' + welcome;

Let and Var
if (name === "sinuna"){
let abc = 'sinuna'; 

//let le yo abc ko scope yo block of code ma matra

let abc = 'sinuna'; 

//var le scope bahira ni chalauna milxa
console.log('abc', abc);
var abc = 'xyz';
}else if {
console.log('abc', abc); xyz
} else {
console.log('abc', abc);
}

functional scope (local scope):

//abc can be used until the block of code
}
console.log(hi('sinuna'));

function hello(arg){ 

//hello is global scope hoisting javascript Hoisting is JavaScript's default behavior of moving declarations to the top.

//function use before function declaration is hoisting

//hoisting is a process of moving all the declaration to the top of module (any js file)
return 'Hello ' + arg + ' ' + welcome
}
console.log(hello('nabin')); 

Example 1:
var getName = function(){  //getName is global scope
}

Example 2: 
var getName = function(){
"use strict"
pqr = "I am inside getName";
}
getName();