const fs = require('fs');

fs.readFile('./file/lorem.txt', (err, data) => {
    if ( err) throw err;
    console.log(data.toString());
    
})

const fs = require("fs");
const path = require("path");

fs.readFile(
  path.join(__dirname, "files", "starter.txt"),
  "utf8",
  (err, data) => {
    if (err) throw err;
    console.log(data);
  }
);

console.log("Hello...");

fs.writeFile(
  path.join(__dirname, "files", "reply.txt"),
  "Nice to meet you.",
  (err) => {
    if (err) throw err;
    console.log("Write complete");

    fs.appendFile(
      path.join(__dirname, "files", "reply.txt"),
      "\n\nYes it is. ",
      (err) => {
        if (err) throw err;
        console.log("Append complete");

        fs.rename(
          path.join(__dirname, "files", "reply.txt"), path.join(__dirname, 'files', 'newReply.txt'),
          (err) => {
            if (err) throw err;
            console.log("Rename complete"); 
          }
        );
      }
    );
  }
);

nodemon index.js

npm install -g nodemon

var nodemailer = require('nodemailer');

var transporter = nodemailer.createTransport({
  service: 'gmail',
  auth: {
    user: 'youremail@gmail.com',
    pass: 'yourpassword'
  }
});

var mailOptions = {
  from: 'youremail@gmail.com',
  to: 'myfriend@yahoo.com',
  subject: 'Sending Email using Node.js',
  text: 'That was easy!'
};

transporter.sendMail(mailOptions, function(error, info){
  if (error) {
    console.log(error);
  } else {
    console.log('Email sent: ' + info.response);
  }
});