Frontend Developer Interview Questions
Frontend Developer Interview Questions
Prep for the interview and get the job you want
About the Book
Your next job interview is a crucial moment in your life, to land your dream job you must prepare for the most challenging questions you might have during the interview. This book is a collection of questions and answers that will help you get ready for that important moment.
More than 80 questions with answers splitted in 3 chapters covering:
- HTML
- CSS
- Javascript
Plus a Free Gift inside for you !!
Check out other books from the author:
Up to Speed with Javascript in 59 minutes
Learning Python Programming from Scratch
Backend Developer Interview Questions
About the Author
Bundles that include this book
Table of Contents
- Other Books by Alejandro
- Your Free Gift
-
Introduction
- Who is this book for ?
- What this book covers ?
-
Chapter 1: HTML Interview Questions
- What does a DOCTYPE do?
- How do you serve a page with content in multiple languages?
- What kind of things must you be wary of when designing or developing for multilingual sites?
-
What are
data-attributes good for? - Consider HTML5 as an open web platform. What are the building blocks of HTML5?
-
Describe the difference between a
cookie,sessionStorageandlocalStorage. -
Describe the difference between
<script>,<script async>and<script defer>. -
Why is it generally a good idea to position CSS
<link>s between<head></head>and JS<script>s just before</body>? Do you know any exceptions? - What is progressive rendering?
-
Why you would use a
srcsetattribute in an image tag? Explain the process the browser uses when evaluating the content of this attribute. - Have you used different HTML templating languages before?
-
Chapter 2: CSS Interview Questions
- What is CSS selector specificity and how does it work?
- What’s the difference between “resetting” and “normalizing” CSS? Which would you choose, and why?
-
Describe
floats and how they work. -
Describe
z-indexand how stacking context is formed. - Describe Block Formatting Context (BFC) and how it works.
- What are the various clearing techniques and which is appropriate for what context?
- Explain CSS sprites, and how you would implement them on a page or site.
- How would you approach fixing browser-specific styling issues?
- How do you serve your pages for feature-constrained browsers? What techniques/processes do you use?
- What are the different ways to visually hide content (and make it available only for screen readers)?
- Have you ever used a grid system, and if so, what do you prefer?
- Have you used or implemented media queries or mobile-specific layouts/CSS?
- Are you familiar with styling SVG?
- Can you give an example of an @media property other than screen?
- What are some of the “gotchas” for writing efficient CSS?
- What are the advantages/disadvantages of using CSS preprocessors?
- Describe what you like and dislike about the CSS preprocessors you have used.
- How would you implement a web design comp that uses non-standard fonts?
- Explain how a browser determines what elements match a CSS selector.
- Describe pseudo-elements and discuss what they are used for.
- Explain your understanding of the box model and how you would tell the browser in CSS to render your layout in different box models.
-
What does
* { box-sizing: border-box; }do? What are its advantages? -
What is the CSS
displayproperty and can you give a few examples of its use? -
What’s the difference between
inlineandinline-block? -
What’s the difference between a
relative,fixed,absoluteandstatically positioned element? - What existing CSS frameworks have you used locally, or in production? How would you change/improve them?
- Have you played around with the new CSS Flexbox or Grid specs?
- Can you explain the difference between coding a website to be responsive versus using a mobile-first strategy?
- How is responsive design different from adaptive design?
- Have you ever worked with retina graphics? If so, when and what techniques did you use?
-
Is there any reason you’d want to use
translate()instead ofabsolutepositioning, or vice-versa? And why?
-
Chapter 3: Javascript Interview Questions
- Explain event delegation
-
Explain how
thisworks in JavaScript - Explain how prototypal inheritance works
- What do you think of AMD vs CommonJS?
-
Explain why the following doesn’t work as an IIFE:
function foo(){ }();. What needs to be changed to properly make it an IIFE? -
What’s the difference between a variable that is:
null,undefinedor undeclared? How would you go about checking for any of these states? - What is a closure, and how/why would you use one?
-
Can you describe the main difference between a
.forEachloop and a.map()loop and why you would pick one versus the other? - What’s a typical use case for anonymous functions?
- How do you organize your code? (module pattern, classical inheritance?)
- What’s the difference between host objects and native objects?
-
Difference between:
function Person(){},var person = Person(), andvar person = new Person()? -
What’s the difference between
.calland.apply? -
Explain
Function.prototype.bind. -
When would you use
document.write()? - What’s the difference between feature detection, feature inference, and using the UA string?
- Explain Ajax in as much detail as possible.
- What are the advantages and disadvantages of using Ajax?
- Explain how JSONP works (and how it’s not really Ajax).
- Have you ever used JavaScript templating? If so, what libraries have you used?
- Explain “hoisting”.
- Describe event bubbling.
- What’s the difference between an “attribute” and a “property”?
- Why is extending built-in JavaScript objects not a good idea?
-
Difference between document
loadevent and documentDOMContentLoadedevent? -
What is the difference between
==and===? - Explain the same-origin policy with regards to JavaScript.
- Make this work:
- Why is it called a Ternary expression, what does the word “Ternary” indicate?
-
What is
"use strict";? What are the advantages and disadvantages to using it? -
Create a for loop that iterates up to
100while outputting “fizz” at multiples of3, “buzz” at multiples of5and “fizzbuzz” at multiples of3and5. - Why is it, in general, a good idea to leave the global scope of a website as-is and never touch it?
-
Why would you use something like the
loadevent? Does this event have disadvantages? Do you know any alternatives, and why would you use those? - Explain what a single page app is and how to make one SEO-friendly.
- What is the extent of your experience with Promises and/or their polyfills?
- What are the pros and cons of using Promises instead of callbacks?
- What are some of the advantages/disadvantages of writing JavaScript code in a language that compiles to JavaScript?
- What tools and techniques do you use for debugging JavaScript code?
- What language constructions do you use for iterating over object properties and array items?
- Explain the difference between mutable and immutable objects.
- How can you achieve immutability in your own code?
- Explain the difference between synchronous and asynchronous functions.
- What is event loop? What is the difference between call stack and task queue?
-
Explain the differences on the usage of
foobetweenfunction foo() {}andvar foo = function() {} -
What are the differences between variables created using
let,varorconst? - What are the differences between ES6 class and ES5 function constructors?
- Can you offer a use case for the new arrow ⇒ function syntax? How does this new syntax differ from other functions?
- What advantage is there for using the arrow syntax for a method in a constructor?
- What is the definition of a higher-order function?
- Can you give an example for destructuring an object or an array?
- ES6 Template Literals offer a lot of flexibility in generating strings, can you give an example?
- Can you give an example of a curry function and why this syntax offers an advantage?
- What are the benefits of using spread syntax and how is it different from rest syntax?
- How can you share code between files?
- Why you might want to create static class members?
- Keep developing your interviewing skills
- About the Author
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