Node.js - timers module

setTimeout(() => {
  const buffer1 = Buffer.from('Hello');
  const buffer2 = Buffer.from('learner');
  const bufferArray = [buffer1, buffer2];
  const bufferConcat = Buffer.concat(bufferArray);

  console.log(bufferConcat.toString());
}, 3000);

setImmediate(() => {
  console.log("I got called right away!");
})