Javascript Modules
Modern JavaScript development depends on modules in which code is split into smaller, reusable and maintainable code. First try to understand the problem,if you have single file //app.js function a...

Source: DEV Community
Modern JavaScript development depends on modules in which code is split into smaller, reusable and maintainable code. First try to understand the problem,if you have single file //app.js function add(a,b) return a +b function multiply(a,b)return a*b Now as code grows Files becomes too large Code becomes hard to read Duplication arise Resuing the code is painful This where modules comes into picture: What is Module A module is simply a file that contains code(function, variables, classes)that you export and reuse into another files. Exporting function or variables export const PI = 3.14 export function add(a,b){ return a+b } You can export multiple things from a module Importing Modules To use export Modules,you import it // app.js import { add, PI } from './math.js'; console.log(add(2, 3)); // 5 console.log(PI); // 3.14 You must use exact name when importing modules. Default vs Named Exports Default Export: A module can have one default export // greet.js export default function greet(