The questions below were asked in a preliminary check before the actual interview. The role itself was for a “JavaScript Engineer”. This particular set of questions is from a job I applied to over a year ago. I’ve chosen to share them here because I think readers of this blog would benefit from knowing what kind of things are expected if you’re applying to a JavaScript-centric role.

  • What is the relationship between ECMAScript, Javascript and Jscript?

  • What core types are available in Javascript?

  • What do the following statements return and why?

    "1" + 2 + 3;
    3 + 2 + "1";
    "1" == 1;
    "1" === 1;
    "1" == true;
    "1" === false;
  • Alert the contents of the bar variable using the foo variable

    var foo = "bar";
    var bar = "foobar";
  • Alert the string “foobar” after a 10 second delay.

  • Implement Array.prototype.filter for IE.

  • Create a Person class with public/private/privileged members and methods.

  • Why does the statement 5 * 1.015 not return 5.075?

  • Replace the string "The quick brown fox jumps over the lazy dog" with the string "The1 quick2 brown3 fox4 jumps5 over6 the7 lazy8 dog9".

  • List several ways that you can communicate asynchronously with the server.

  • How would you embed this URL in a link inside an XHTML document?
  • How would you serve a StyleSheet only to IE users older than IE8?

  • Write a jQuery plugin to display a list of images in a Lightbox.

What do you think of these questions? Fair?


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