What is This

// Open up a console in chrome and follow along
// Global context
this // Returns Window Object// Function in global context function globalFunc() {
return this
globalFunc() // Returns Window Object
globalFunc() === this // true
// Class Instance Methodclass Person {
constructor(firstName, lastName) {
this.firstName = firstName // Sets first name
this.lastName = lastName // Sets last name
sayName() {
// this refers to instance of class
console.log(this.firstName + ' ' + this.lastName)
let johnSmith = newPerson('John', 'Smith') // Instantiate new person
johnSmith.sayName() // Logs 'John Smith' to console
// Event Handlerslet body = document.getElementsByTagName('body')[0]
body.addEventListener('click', function(e) {
console.log(this) // logs body element when body is clicked
this // returns Window Objectlet body = document.getElementsByTagName('body')[0];body.addEventListener('click', function(e) {
// On click, logs Window Object to Console
// Without .bind(this), it would log the body element to the console
let person = {
name: 'John Smith',
sayName: function() {
console.log('My name is ' + this.name)
let car = {
name: 'Herbie'
let sayName = person.sayName.bind(car)
person.sayName() // My name is John Smith
sayName() // My name is Herbie




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