Frontend Interview Questions

The most common frontend interview questions

JavaScript (22)HTML (3)CSS (6)React (9)Browser (14)Webpack (2)Web Security (3)Performance Optimization (2)Frontend Architecture (4)

▪︎ In JavaScript, what is the difference between ==, === and Object.is()

▪︎ Please explain the difference between null, undefined and undeclared

▪︎ Please explain the difference between var, let and const

▪︎ Describe how this keyword works in JavaScript?

▪︎ How to use call, apply or bind in JavaScript?

▪︎ What is hoisting in JavaScript?

▪︎ Please explain the event loop

▪︎ What is a promise?

▪︎ What is the difference between Promise.all and Promise.race?

▪︎ Please explain async/await

▪︎ What is a closure, and how/why is it used?

▪︎ Tell me about your understanding of prototypes and prototype chains

▪︎ What does new keyword in JavaScript do?

▪︎ What is the difference between spread syntax and rest syntax? When will it be used

▪︎ What is new in ES6? / What is new in the latest ES version?

▪︎ Please explain how event delegation works

▪︎ What is the difference between an arrow function and a normal function

▪︎ Please explain the difference between Map and object, and how would you choose which one to use?

▪︎ The difference between event.target and event.currentTarget

▪︎ What is the difference between Map and WeakMap?

▪︎ Please explain the way to operate an array? How to do it immutably?

▪︎ what will the push method of an array return?