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  1. null vs undefined?
const name = null;
console.log(name); // null
const name;
console.log(name); // undefined

  1. What is React?

  1. Hoisting: Hoisting is a Javascript by default behavior. It moves all the declaration at the top of the current scope (top of the function or script). This is called hoisting. Don’t understand? See the code below-
function getStudentName(info) {    if(info) {
var name = 'Rakib';
return name;
} else {
return null;
function getStudentName(info) {
var name;
if(info) {…

  1. The map method allows you to loop through all the elements and allows you to execute the function to all the elements of the calling array and it returns a new array.

Md Rakib

Web Developer (MERN Stack)

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