node js tutorial

// append_file.js

const fs = require('fs');

// add a line to a lyric file, using appendFile
fs.appendFile('empirestate.txt', '\nRight there up on Broadway', (err) => {
    if (err) throw err;
    console.log('The lyrics were updated!');
});

The website below has a great tutorial for beginners.
It explains all the basics you need to know without
overloading you with complexities.
Naturally you can advance to these complexities once
you have the base knowledge.

  var http = require('http');

http.createServer(function (req, res) {
  res.writeHead(200, {'Content-Type': 'text/plain'});
  res.end('Hello World!');
}).listen(8080);  

www.w3schools.com/nodejs/