index.js

const fs = require('fs');

const setTimeOutlogger = ()=>{
    console.log('setTimeout logger');
}
const setImmediateLogger = ()=>{
    console.log('setImmediate logger');
}

//For timeout 
setTimeout(setTimeOutlogger, 1000);

//File I/O operation
fs.readFile('test.txt', 'utf-8',(data)=>{
    console.log('Reading data 1');
});
fs.readFile('test.txt', 'utf-8',(data)=>{
    console.log('Reading data 2');
});
fs.readFile('test.txt', 'utf-8',(data)=>{
    console.log('Reading data 3');
});
fs.readFile('test.txt', 'utf-8',(data)=>{
    console.log('Reading data 4');
});
fs.readFile('test.txt', 'utf-8',(data)=>{
    console.log('Reading data 5');
});

//For setImmediate
setImmediate(setImmediateLogger);
setImmediate(setImmediateLogger);
setImmediate(setImmediateLogger);