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JavaScript Interview Questions | FineFrontend

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JavaScript

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JavaScript interview questions

Core concepts, async, prototypes, and advanced patterns.

20 of 48 questions loaded

01Question 1: What is JavaScript?

02Question 2: What are the data types in JavaScript?

03Question 3: What is the difference between let, const, and var?

04Question 4: What is hoisting?

05Question 5: What is the DOM?

06Question 6: What is an event listener?

07Question 7: What is the difference between == and ===?

08Question 8: What is NaN?

09Question 9: Explain undefined vs null.

10Question 10: How do you add an element to an array?

11Question 11: What is a closure?

12Question 12: What is an arrow function?

13Question 13: What does 'use strict' do?

14Question 14: How do you check the type of a variable?

15Question 15: What is the purpose of the this keyword?