2/4/2016 - 7:17 PM

JS Interview questions

JS Interview questions

Javascript Interview Questions

General interview questions for a front-end JS developer.


  • What is the spec Javascript implements and what versions of it are you most current with?

  • Does JavaScript support the use of classes?

  • What is the prototype of an object?

  • What is prototypal inheritance?

  • What is the DOM?

  • What are the two types of event propagation?

  • What is the difference between event bubbling and event capturing for DOM events?

  • What is the “this” keyword and what does it reference?

  • How does scope in Javascript differ from other languages?

  • What is hoisting?

  • What is a closure?

  • What is the module pattern and what problem does it attempt to solve?

  • What is dependecy injection?

  • Do you have any experience with RequireJS or CommonJS?

  • What front end frameworks have you worked with before?

  • Have you ever worked with AngularJS?

  • What are directives and how are they used?

  • What are services and what purpose do they serve?

  • What's your favorite thing about JS?

  • What is your least favorite thing about JS?

  • Generally speaking, what is the slowest operation you can perform on the front-end with JS?

  • What does the 'use strict' declaration do?

  • What different in the arguments variable in a function when 'use strict' is declared?

  • What kinds of techniques can you use to call a web service from another domain?

  • What is a CORS request?

  • What browsers support CORS requests?

  • How do you do a CORS request in IE9 and what caveats must you work around?

  • What does the defer attribute do when loading a script tag?

  • What is Cross-Site Scripting?

  • What is the Same Origin Policy?

  • What is Cross-Site Request Forgery?

  • What are some of the new JavaScript features in HTML5?

  • What is a WebSocket?

  • What is test driven development?

  • What's the difference between a unit test and an integration test?

  • What is NodeJs?

  • What engine powers NodeJs?


  1. Write a function that will iterate over an array of emails and will call sendEmail({email}) with each item.
  2. Write a function that will return the manager of a user from a nested heirarchy.