How I wish there was a documentation that shows me a detailed explanation of what's happening in a Hello World example.

Well. Instead of wishing, I started to craft a nice visual for my own and I hope this would help others as well.

Some basic explanations:

What is Node.js?

  • An open source server environment.
  • It allows you to run JavaScript on the server.

Node.js uses asynchronous programming

  • generate dynamic page content
  • create, open, read, write, delete, and close files on the server
  • collect form data
  • add, delete, and modify data in your database

HTTP Server

function and parameters req and res

Status code


Finishing the request

Listening to the port

Things you need to run this on your machine:

  1. Install VSCode:
  2. Install Node.js:
  3. Create a file named app.js.
  4. Copy the code below.
  5. In your terminal, execute node app.js.
  6. In your browser, type http://localhost:8080/ and hit Enter.
var http = require('http');

http.createServer(function (req, res) {
  res.writeHead(200, {'Content-Type': 'text/plain'});
  res.end('Hello World!');