41 of 41 questions
// Interview Deck · JAVASCRIPT
JavaScript
Closures, hoisting, event loop, async patterns, and the core language concepts behind every framework.
01
Beginner
Difference between var, let, and const?
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02
Beginner
What is hoisting in JavaScript?
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03
Beginner
What is a closure? Give an example.
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04
Intermediate
How does the 'this' keyword behave in different contexts?
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05
Advanced
Explain the event loop, call stack, and microtasks vs macrotasks.
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06
Intermediate
What is a Promise and what are its states?
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07
Intermediate
Explain async/await and how it relates to Promises.
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08
Beginner
What is a callback function and what is 'callback hell'?
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09
Beginner
What is a higher-order function?
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10
Beginner
Explain map, filter, and reduce.
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11
Beginner
Difference between == and ===?
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12
Beginner
Explain scope — global, function, and block scope.
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13
Intermediate
What is the Temporal Dead Zone (TDZ)?
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14
Beginner
Difference between arrow functions and regular functions?
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15
Beginner
Difference between null and undefined?
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16
Intermediate
What is type coercion in JavaScript?
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17
Intermediate
Difference between event bubbling and event capturing?
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18
Intermediate
What is event delegation?
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19
Intermediate
Difference between debounce and throttle?
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20
Advanced
Explain the prototype and prototypal inheritance.
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21
Intermediate
Difference between call, apply, and bind?
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22
Beginner
Difference between spread and rest operator?
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23
Beginner
What is destructuring in JavaScript?
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24
Beginner
What are template literals?
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25
Beginner
Difference between map and forEach?
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26
Intermediate
What are Set and Map objects?
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27
Intermediate
Difference between shallow copy and deep copy?
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28
Intermediate
What are pure functions and why does immutability matter?
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29
Beginner
How does try/catch/finally work for error handling?
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30
Intermediate
What is an IIFE (Immediately Invoked Function Expression)?
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31
Beginner
How do you access localStorage and sessionStorage using JS?
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32
Beginner
Difference between setTimeout and setInterval?
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33
Advanced
What is currying in JavaScript?
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34
Advanced
What is memoization?
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35
Intermediate
What are optional chaining and nullish coalescing?
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36
Intermediate
Difference between ES Modules (import/export) and CommonJS (require)?
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37
Beginner
What is NaN and how do you check for it?
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38
Advanced
What are generators and iterators?
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39
Advanced
What is the Symbol data type?
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40
Beginner
What is 'use strict' and what does it do?
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41
Beginner
Difference between 'not defined' and undefined?
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