Front-end-Developer-Interview-Questions: A repository from donatkinson

#JOB INTERVIEW QUESTIONNAIRE

@version 1.0

##Contributors

@bentruyman (http://bentruyman.com/), @roger_raymond (http://twitter.com/iansym), @ajpiano (http://ajpiano.com/), @paul_irish (http://paulirish.com/), @SlexAxton (http://alexsexton.com/), @boazsender (http://boazsender.com/), @miketaylr (http://miketaylr.com/), @vladikoff (http://vladfilippov.com/), @gf3 (http://gf3.ca/), @jon_neal (http://twitter.com/jon_neal), @wookiehangover (http://wookiehangover.com/) and @darcy_clarke (http://darcyclarke.me)

General Questions:

Are you on Twitter?
- If so, who do you follow on Twitter?
Are you on Github?
- If so, what are some examples of repos you follow
What blogs do you follow?
What version control systems have you used?
What is your preferred development enviroment? (OS, Editor, Browsers, Tools etc.)
Can you describe your workflow when you create a web page?
Can you describe the difference between progressive enhancement and graceful degredation?
- Bonus points for the answer "no one can"
- Extra bonus points for describing feature detection
Explain what "Semantic HTML" means.
What does "minification" do?
Why is it better to serve site assets from multiple domains?
- How many resources will a browser download from a given domain at a time?
If you have 8 different stylesheets for a given design, how would you integrate them into the site?
- Looking for file concatenation.
- Points off for @import, unless it works in conjunction with a build system.
If you jumped on a project and they used tabs and you used spaces, what would you do?
- issue :retab! command
Write a simple slideshow page
- Bonus points if it does not use JS.
What tools do you use to test your code's performance?
If you could master one technology this year, what would it be?
Name 3 ways to decrease page load. (perceived or actual load time)
Explain the importance of standards.

HTML-Specific Questions:

What's a doctype do, and how many can you name?
What's the difference between standards mode and quirks mode?
What are the limitations when serving XHTML pages?
- Are there any problems with serving pages as application/xhtml+xml?
How do you serve a page with content in multiple languages?
Can you use XHTML syntax in HTML5? How do you use XML in HTML5?
What are data- attributes good for?
What are the content models in HTML4 and are they different in HTML5?
Consider HTML5 as an open web platform. What are the building blocks of HTML5?
Describe the difference between cookies, sessionStorage and localStorage.

JS-Specific Questions

Which JavaScript libraries have you used?
How is JavaScript different from Java?
What are undefined and undeclared variables?
What is a closure, and how/why would you use one?
- Your favorite pattern used to create them? argyle (Only applicable to IIFEs)
What's a typical use case for anonymous functions?
Explain the "JavaScript module pattern" and when you'd use it.
- Bonus points for mentioning clean namespacing.
- What if your modules are namespace-less?
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() var person = new Person()

What's the difference between .call and .apply?
explain Function.prototype.bind?
When do you optimize your code?
Can you explain how inheritance works in JavaScript?
- Bonus points for the funny answer: "no one can"
- Extra bonus points if they take a stab at explaining it
When would you use document.write()?
- Correct answer: 1999 - time to weed out the junior devs
What's the difference between feature detection, feature inference, and using the UA string
Explain AJAX in as much detail as possible
Explain how JSONP works (and how it's not really AJAX)
Have you ever used JavaScript templating, and if so, what/how?
Explain "hoisting".
What is FOUC? How do you avoid FOUC?
Describe event bubbling.
What's the difference between an "attribute" and a "property"?
Why is extending built in JavaScript objects not a good idea?
Why is extending built ins a good idea?
Difference between document load event and document ready event?
What is the difference between == and ===?
Explain how you would get a query string parameter from the browser window's URL.
Explain the same-origin policy with regards to JavaScript.
Explain event delegation.
Describe inheritance patterns in JavaScript.
Make this work:

[1,2,3,4,5].duplicator(); // [1,2,3,4,5,1,2,3,4,5]

Describe a strategy for memoization (avoiding calculation repetition) in JavaScript.
Why is it called a Ternary statement, what does the word "Ternary" indicate?
What is the arity of a function?

JS-Code Examples:

>~~3.14

Question: What value is returned from the above statement? Answer: 3

"i'm a lasagna hog".split("").reverse().join("");

Question: What value is returned from the above statement? Answer: "goh angasal a m'i"

( window.foo || ( window.foo = "bar" ) );

Question: What is the value of window.foo? Answer: "bar" if intially window.foo was false, undefined or zero else it will retain its value.

var foo = "Hello"; (function() { var bar = " World"; alert(foo + bar); })(); alert(foo + bar);

Question: What is the outcome of the two alerts above? Answer: "Hello World" & ReferenceError: bar is not defined

jQuery-Specific Questions:

Explain "chaining".
What does .end() do?
How, and why, would you namespace a bound event handler?
What is the effects (or fx) queue?
What is the difference between .get(), [], and .eq()?
What is the difference between .bind(), .live(), and .delegate()?
What is the difference between $ and $.fn? Or just what is $.fn.
Optimize this selector:

$(".foo div#bar:eq(0)")

CSS-Specific Questions:

Describe what a "reset" CSS file does and how it's useful.
Describe Floats and how they work.
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.
What are the differences between the IE box model and the W3C box model?
What are your favourite image replacement techniques and which do you use when?
CSS property hacks, conditionally included .css files, or... something else?
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 screenreaders)?
Have you ever used a grid system, and if so, what do you prefer?
Hav you used or implement media queries or mobile specific layouts/CSS?
Any familiarity with styling SVG?
How do you optimize your webpages for print?
What are some of the "gotchas" for writing efficient CSS?
Do you use LESS?
How would you implement a web design comp that uses non-standard fonts? (avoid mentioning webfonts so they can figure it out)
Explain how a browser determines what elements match a CSS selector?

Optional fun Questions:

What's the coolest thing you've ever coded, what are you most proud of?
Do you know the HTML5 gang sign?
Are you now, or have you ever been, on a boat.
Tell me your favorite parts about Firebug / Webkit Inspector.
Do you have any pet projects? What kind?
Explain the significance of "cornify".
On a piece of paper, write down the letters A B C D E vertically. Now put these in descending order without writing one line of code.
- Wait and see if they turn the paper upside down
This should make the laugh and is a fine way to relieve some tension at the end of the interview.
Pirate or Ninja?
- Bonus if it's a combo and a good reason was given (+2 for zombie monkey pirate ninjas)
If not Web Development what would you be doing?
Where in the world is Carmen Sandiego? (hint: their answer is always wrong)
What's your favorite feature of Internet Explorer?
Complete this sentence: Brendan Eich and Doug Crockford are the __________ of javascript.
jQuery: a great library or the greatest library? Discuss.