InterviewsTop 10 Front End Developer Interview Questions & Answers

Top 10 Front End Developer Interview Questions & Answers

Given the fact that you are prepping for an interview that will help you grab the exciting role of a front-end developer, here is the list of 10 technical questions and answers that can help you get a gist of the quesitons that you can may face. Just scan through these commonly posed questions and their answers as your last-minute homework and you are all set to impress the interview panel with your technical skills concerning front-end development.

You as a prospective candidate for the job of a Front-End Developer will be asked to answer a couple of fundamental questions such as:

Q1. What makes up a good Front-End Developer? What are his responsibilities?

Before speaking about who a Front-End Developer is, it is important to know what front-end is all about. Front-End, for a website, concerns all the components that the user accesses as part of his interactions with the website. So, it is all about the inclusion of buttons, color schemes, images, forms, animations and typography.

So, the job of a front-end developer basically involves the creation of user-friendly components of a website. He is a software programmer who writes codes for all the features of a website that will improve its functionality, in a number of creative ways. Making the best use of his innovative and creative web development skills, it is the prime responsibility of a front-end developer to ensure that the look and feel of a particular website is uniform across different web browsers.

Q2. Can you list all the technical and additional skills that are required by a front-end developer?

A good front-end developer should have working knowledge about:

  • CSS
  • HTML
  • JavaScript
  • JQuery

Apart from the above mentioned technical skills, a front-end developer will become an asset to an organization provided he possess the below mentioned “good-to-have” skills.

  • Basic knowledge about SEO and tools like Dreamweaver and Flash which are used to present web-based information to end users
  • Information about cross browser testing
  • Knowledge of any of the Content Management Systems (CMS) like Drupal, WordPress and Joomla
  • Knowledge about Object Oriented Programming languages like OOPS and PHP

Q3. Can you explain what Three.js is and quote its key features?

Three.js is an open-source JavaScript 3D library that allows you to create and display animated 3D computer graphics in a web browser. This is an API which uses WebGL to create impressive web demonstrations. And the best part of Three.js is that you can display all these graphics without depending on exclusive plug-ins.

Important features of Three.js along with their various functions are:

  • Renderers: – canvas, svg, WebGL, CSS3D, DOM, Software; effects: stereo, cross-eyed.
  • Shaders: – You can completely access GLSL capabilities which include: lens flare, depth pass and the all-in-one post-processing library.
  • Scenes: – You can add or delete objects at run-time.
  • Cameras: – Allows you to make the most of Orthographic and Perspective controllers like Trackball, FPS and Path.
  • Lights: – This feature allows you to flip between various lighting options like spot and point lights, additionally permitting you to cast and receive shadows.
  • Animations: – You can morph and perform Keyframe operations.
  • Materials: – Your website can sport a smooth-shading, with various options coming in the form of textures and sheen. Phong, depth, lambert and face are some of the capabilities that you can employ.
  • Objects: – Through this feature, you can create meshes, lines, sprites, ribbons and particles
  • Geometry: – Modifiers like tube, lathe and extrude are available along with facilities to draw geometrical figures like cubes, spheres and cylinders
  • Export/Import: – With this feature, you can work with CTM, Blender, FBX and OBJ
  • Debugging: – WebGL Inspector, Stats.js and Three.js inspector are the features under this head
  • Loaders: – This feature facilitates JSON, binary, scene, XHR and Image
  • Support: – You can check out the world of information that is available in the form of public forum, API documentation and Wiki

After answering the above questions, you may be asked a series of questions related to CoffeeScript. They are:

Q4. What is CoffeeScript? What are the Ways in which CoffeeScript is Superior to JavaScript?

CoffeeScript is a small programming language that helps you fine tune JavaScript code. This language which compiles into JavaScript is a perfect alternative to the irregular syntax of JavaScript. Consistency in syntax is what makes CoffeeScript superior to JavaScript. Here are the basic rules for CoffeeScript:

  • Absence of curly braces
  • Functions that take arguments do not need parentheses

CoffeeScript is a better option compared to JavaScript on account of the following inherent advantages.

  • CoffeeScript simplifies your daily programming chores in contrast to JavaScript.
  • CoffeeScript cuts down on coding requirements and permits you to express your program with small codes, when compared to JavaScript.
  • Through CoffeeScript, you can make the most of the lightweight add-ons like Python style list comprehension and Ruby string interpolation.

Q5. How are the variables of CoffeeScript different from those of JavaScript?

In JavaScript, variables need to end with a semi-colon for them to be executed. However, with CoffeeScript, there is no necessity to add a semi-colon at the end of every statement. Hence, CoffeeScript simplifies the process of adding a semi-colon to variables.

Q6. What are the fundamental rules to remember when using CoffeeScript?

The two basic rules for CoffeeScript are:

  1. Importance is given to whitespaces, which is why it doesn’t require curly braces.
  2. The absence of parentheses is another rule of CoffeeScript. Through this, you can write functions to take arguments without the need of parentheses.

Q7. Can you explain the functions in CoffeeScript?

“Functions” in CoffeeScript is a list of parameters which follow an arrow after which you have the function body. This is an optional list. For instance: log = (message) à console.log message.

Q8.What are the applications of clone-function in CoffeeScript?

If you wish to create a completely new object in CoffeeScript, you can rely on the Clone function. You can do this in the following ways:

  • You need to copy all the attributes from the source object to the new object
  • You then need to repeat all the steps of copying attributes from the source object for all the sub-objects. To perform this function, you need to call the Clone function
  • The last step allows you to create a new object similar to the source object

Q9. Can you briefly explain what a Thread-Local object in Python Flask is?

Through Python Flask, front-end developers use thread local objects internally. This is a function of user-friendliness which does not require the user to pass objects around from one function to another. This paves the way to process a request alongside permitting to operate in a “threadsafe” condition. Although this approach is worthwhile, it is essential to obtain a valid request context for dependency injection or when you are trying to reuse the code which employs a value tagged to the request.

Q10. Can you list the differences between WebGL and Three.js?

There are 3 main differences between WebGL and Three.js.



WebGL facilitates a direct control over the GPU

Three.js is built on top of WebGL and allows you to exercise control over a lot of activities including what objects should be used to draw a certain frame

WebGL is characterized by an “immediate mode”

Three.js manifests a “retained mode”

WebGL does not offer additional support for shaders and text

Three.js offers additional support for text, object hierarchy and for picking

Conclusion: –
A quick glance at this Q&A format will assist you with your just-in-time preparation for that job interview that you have longed to crack. The moment you have answered all the technical questions posed by the interview panel, you are just a step away to getting offered by the hiring manager of your dream company. After you accept the offer, you can proudly carry the tag of a competent and well-informed Front-End Developer adept at churning out user-friendly websites to clients.


Please enter your comment!
Please enter your name here

Exclusive content

- Advertisement -

Latest article


More article

- Advertisement -