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JavaScript (31)
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  • What Are the Primitive Types in JavaScript? How To Check the Type of a Variable?

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  • In JavaScript, what is the difference between ==, === and Object.is()

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  • What Is the Difference Between null, undefined and undeclared in JavaScript?

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  • What is the Difference Between Map and Object in JavaScript, and Why Do We Need Map?

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  • What Is the Difference Between Set, Map, WeakSet, and WeakMap in JavaScript?

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  • What Will 0.1 + 0.2 Be in JavaScript? Why?

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  • What Is the Purpose of "use strict" in JavaScript and What Are the Benefits of Using It?

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  • What Is the Difference Between var, let and const in JavaScript?

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  • What Is the Scope and Scope Chain of JavaScript?

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  • What Is JavaScript Closure?

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  • Explain what hoisting is in JavaScript

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  • Different Ways of Iterating an Array in JavaScript? What Is the Difference Between Them?

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  • In JavaScript Built-In Sort, When You Pass in (a, b) => b – a, How Will It Sort the Array? Why?’

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  • What Is an Arrow Function in JavaScript? How Is It Different From a Regular Function?

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  • What is an IIFE (Immediately Invoked Function Expression) in JavaScript? What are the Pros and Cons?

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  • What Is a Higher-Order Function in JavaScript?

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  • Tell me about your understanding of prototypes and prototype chains

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  • What Is "this" in JavaScript?

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  • How to use call, apply or bind in JavaScript?

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  • Explaining the Concept of a Class in ES6 and the Distinction Between a Function Constructor

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  • What Is an Event Loop in JavaScript?

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  • What Is JavaScript Promise? And How To Use It?

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  • What is the difference between Promise.all and Promise.race?
  • Please explain async/await
  • What does new keyword in JavaScript do?
  • What is the difference between spread syntax and rest syntax? When will it be used
  • What is new in ES6? / What is new in the latest ES version?

  • Please explain how event delegation works

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  • The difference between event.target and event.currentTarget
  • Please explain the way to operate an array? How to do it immutably?
  • what will the push method of an array return?