Node.js Events Every action on a computer is an event. Node.js object can fire an event like readStream object fires events when opening and closing a file. var fs = require('fs'); var rs = fs.createReadStream('./demo.txt'); rs.on('open', function () { console.log('The file is open'); }); Events Module Node.js has a built-in module, called "Events", where you can create-, fire-, and listen for- your own events. All event properties and methods of event module are an instance of an EventEmitter object. EventEmitter Object var events = require('events'); var eventEmitter = new events.EventEmitter(); //Create an event handler: var myEventHandler = function () { console.log('I hear a scream!'); } //Assign the event handler to an event: eventEmitter.on('scream', myEventHandler); //Fire the 'scream' event: eventEmitter.emit('scream'); ...