Operational Front End Web Developer Interview Questions & Answers:

1. What Is The Difference Between Html And Xhtml?

HTML is HyperText Markup Language used to develop the website.

XHTML is modern version of HTML 4. XHTML is an HTML that follows the XML rules which should be well-formed.

2. Tell us in CoffeeScript how clone-function is useful?

Clone function is useful in creating a complete new object in Coffee Script by

☛ Copying all attributes from the source object to the new object
☛ Repeating the steps of copying attributes from the source object for all sub-objects by calling the clone-function
☛ Creating a new object as the source object

3. Tell me how To Increase Page Performance?

☛ Sprites, compressed images, smaller images;
☛ include JavaScript at the bottom of the page;
☛ minify or concatenate your CSS and JavaScript; and
☛ caching.

4. Explain me functional programming in JavaScript?

Functional programming is one of the key paradigms that makes JavaScript stand out from other languages. Look for examples of functional purity, first-class functions, higher-order functions, or using functions as arguments and values. It's also a good sign if they have past experience working with functional languages like Lisp, Haskell, Erlang, or Clojure.

5. Do you know what is CoffeeScript?

CoffeeScript is a small programming language that compiles into JavaScript. It helps to write JavaScript code better by providing you with a more consistent syntax and avoiding the irregular nature of JavaScript language

The basic rule for Coffee Script:
☛ Whitespace matters: There are no curly braces in CoffeeScript
☛ No parentheses: Functions that take arguments do not require parentheses

6. Tell us why Do We Need To Use W3c Standard Code?

The goals of such standards are to ensure cross-platform compatibility and more compact file sizes. The focus of these standards has been to separate "content" from "formatting" by implementing CSS. It eases maintenance and development.

7. Tell me what Is A Closure?

Closures are expressions, usually functions, which can work with variables set within a certain context. Or, to try and make it easier, inner functions referring to local variables of its outer function create closures.

8. Tell me a time that you used Prototypal OO in JavaScript?

Prototypal OO is the other major programming paradigm that really lets JavaScript shine-objects linked to other objects (OLOO). You're looking for knowledge of when and where to use prototypes, liberal use of “Object.assign()” or mixins, and a solid grasp of concepts like delegation and concatenative inheritance.

9. Please tell me what is a Thread-Local object in Python Flask?

Flask uses thread local objects internally so that user don't have to pass objects around from function to function within a request in order to stay threadsafe. This approach is useful, but it requires a valid request context for dependency injection or when attempting to reuse code which uses a value pegged to the request.

10. Tell me some Common Ie6 Bugs And How You Dealt With Them?

Ie6 is not dead, just ask China which represents a nice chunk of the worlds online population. Your pages should at least be functional on IE6, unless you dont care about half the worlds population.