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Describe the difference between `<script>`, `<script async>` and `<script defer>`
Explain how prototypal inheritance works
Explain how `this` works in JavaScript
What are the differences between variables created using `let`, `var` or `const`?
What is the difference between `==` and `===`?
What's the difference between a variable that is: `null`, `undefined` or undeclared?
How would you go about checking for any of these states?"What's the difference between `.call` and `.apply`?
Describe the difference between a cookie, `sessionStorage` and `localStorage`.
Can you offer a use case for the new arrow => function syntax?
How does this new syntax differ from other functions?Explain `Function.prototype.bind`
Explain the difference between synchronous and asynchronous functions
What are the pros and cons of using Promises instead of callbacks?
What is a closure, and how/why would you use one?
What language constructions do you use for iterating over object properties and array items?
What's a typical use case for anonymous functions?
Difference between: `function Person(){}`, `var person = Person()`, and `var person = new Person()`?
Explain Ajax in as much detail as possible.
Explain how JSONP works (and how it's not really Ajax)
Explain the difference between mutable and immutable objects
Explain what a single page app is and how to make one SEO-friendly
What advantage is there for using the arrow syntax for a method in a constructor?
What are the differences between ES2015 class and ES5 function constructors?
What is the definition of a higher-order function?
What's the difference between an "attribute" and a "property"?
What's the difference between feature detection, feature inference, and using the UA string?
Why is it, in general, a good idea to leave the global scope of a website as-is and never touch it?
Can you describe the main difference between a `.forEach` loop and a `.map()` loop?
Why you would pick one versus the other?Can you give an example for destructuring an object or an array?
Can you give an example of a curry function and why this syntax offers an advantage?
Difference between document `load` event and document `DOMContentLoaded` event?
ES2015 Template Literals offer a lot of flexibility in generating strings, can you give an example?
Explain the same-origin policy with regards to JavaScript
How can you share code between files?
How do you organize your code?
Do you use module pattern, classical inheritance, something else?What are the advantages and disadvantages of using Ajax?
What are the benefits of using spread syntax and how is it different from rest syntax?
What do you think of AMD vs CommonJS?
What is the extent of your experience with Promises and/or their polyfills?
What tools and techniques do you use for debugging JavaScript code?
What's the difference between host objects and native objects?
When would you use `document.write()`?
Why is extending built-in JavaScript objects not a good idea?
Why is it called a Ternary expression, what does the word "Ternary" indicate?
Why would you use something like the `load` event?
Does this event have disadvantages? Do you know any alternatives, and why would you use those?Why you might want to create static class members?