Arrow functions (=>) are a shorter way to write functions in JavaScript. Arrow functions remove function keyword and use => instead.

example :
----- normal function ----
function sum(num1,num2){
const result = num1 + num2;
}

----- arrow function ----
const sum = (num1,num2) => {
const result = num1 + num2;
}

A Promise in JavaScript is used to handle asynchronous operations. It helps to execute code that takes time (like fetching data from an API) without stopping the rest of the program.

What is a Promise?

A Promise is an object that represents the eventual completion or failure of an asynchronous operation.

It has 3 states:

• ✔️ Pending → Initial state (not yet completed).
• ✔️ Fulfilled → The operation was successful.
• ✔️ Rejected → The operation failed.

A closure is when a function remembers the variables from its outer scope, even after the outer function has finished running.

How Closures Work?

A closure is created when:

• ✔️ A function is inside another function.
• ✔️ The inner function uses variables from the outer function.
• ✔️ The inner function is returned or stored, keeping access to the outer variables.