Hi, You are welcome to the “JavaScript tricky questions” article. If you are a student or working professional and you want to improve your coding skills or want to prepare for Interview then this article is for you.
In this article, we present 100+ JavaScript tricky questions that will put your knowledge to the test and help you sharpen your coding skills.
JavaScript is a dynamic and versatile programming language that plays a crucial role in creating interactive web experiences. As a JavaScript developer, it’s important to have a deep understanding of the language’s concepts and nuances.
So, let’s dive into the world of JavaScript and explore these challenging questions to take your expertise to the next level.
30+ JavaScript Tricky Questions for Beginners
If you are a JavaScript Developer at the beginning level, these questions will help you to improve your understanding of JavaScript
Certainly! Here are 30 JavaScript tricky questions suitable for beginners:
- What will be the output of
typeof NaN
? - Explain the difference between
==
and===
in JavaScript. - What is hoisting in JavaScript?
- What is the difference between
let
,const
, andvar
in terms of variable scoping? - How can you check if a variable is an array in JavaScript?
- What is the purpose of the
NaN
value in JavaScript? - Explain the difference between a function declaration and a function expression.
- How can you check if a variable is defined in JavaScript?
- What is the difference between
null
andundefined
? - Explain the concept of scope in JavaScript.
- How can you convert a string to a number in JavaScript?
- What is a callback function in JavaScript?
- Explain the concept of asynchronous programming in JavaScript.
- How can you iterate over an object in JavaScript?
- What is the purpose of the
this
keyword in JavaScript? - Explain the difference between a method and a function in JavaScript.
- How can you create a new object in JavaScript?
- What is a closure in JavaScript?
- Explain the concept of event handling in JavaScript.
- How can you add a new element to an array in JavaScript?
- What is the purpose of the
slice()
method in JavaScript arrays? - Explain the concept of function parameters and arguments in JavaScript.
- How can you remove an element from an array in JavaScript?
- What is the purpose of the
setTimeout()
function in JavaScript? - Explain the difference between synchronous and asynchronous code in JavaScript.
- How can you concatenate two strings in JavaScript?
- What is the purpose of the
push()
method in JavaScript arrays? - Explain the concept of variable scope in JavaScript functions.
- How can you convert a number to a string in JavaScript?
- What is the purpose of the
length
property in JavaScript arrays? - What are the truthy and falsy values in JavaScript?
These questions will help beginners test their understanding of JavaScript concepts and get a grasp of the language’s fundamental principles
You can also learn
- Truthy and Falsy Values in JavaScript Detail Explanation
- Javascript String Methods Cheat Sheet
- 12 Tricks To Write Less JavaScript | JavaScript Tricks
30+ JavaScript Tricky Questions for Intermediate Level
These intermediate-level questions will help you delve deeper into JavaScript concepts and sharpen your problem-solving skills
Certainly! Here are 30 JavaScript tricky questions suitable for intermediate-level developers:
- Explain the concept of hoisting in JavaScript and how it works.
- What is the difference between
null
andundefined
in JavaScript? - How does JavaScript handle asynchronous operations?
- Explain the difference between
let
,const
, andvar
in terms of variable scope. - How can you check if a variable is an object in JavaScript?
- What is a closure in JavaScript and how can it be used?
- Explain the concept of prototypal inheritance in JavaScript.
- What are higher-order functions in JavaScript? Provide an example.
- How can you create a private variable in JavaScript?
- What is event delegation in JavaScript and how does it work?
- Explain the concept of currying in JavaScript.
- How can you deep-clone an object in JavaScript?
- What is the purpose of the
bind()
method in JavaScript? - Explain the difference between synchronous and asynchronous JavaScript code.
- What are the benefits of using arrow functions in JavaScript? Provide examples.
- How can you handle errors and exceptions in JavaScript?
- Explain the concept of function composition in JavaScript.
- What is the purpose of the
reduce()
method in JavaScript arrays? - How can you check if an element exists in an array in JavaScript?
- Explain the concept of variable shadowing in JavaScript.
- What are the different ways to create objects in JavaScript? Provide examples.
- How can you implement memoization in JavaScript?
- Explain the concept of the event loop in JavaScript.
- What is the purpose of the
async
andawait
keywords in JavaScript? - How can you convert a string to an array in JavaScript?
- Explain the concept of destructuring in JavaScript.
- What is the purpose of the
filter()
method in JavaScript arrays? - How can you handle CORS (Cross-Origin Resource Sharing) in JavaScript?
- Explain the concept of functional programming in JavaScript.
- What is the difference between shallow copy and deep copy of an object in JavaScript?
30+ JavaScript Tricky Questions for Higher level Developers
These advanced-level questions will challenge your in-depth understanding of JavaScript concepts and stretch your problem-solving skills. Certainly! Here are 30 JavaScript tricky questions suitable for higher-level developers:
- Explain the concept of function hoisting in JavaScript and its implications.
- What is the difference between prototypal inheritance and classical inheritance in JavaScript?
- How does JavaScript handle memory management and garbage collection?
- Explain the concept of a closure in JavaScript and provide a practical use case.
- What are the differences between the
apply()
,call()
, andbind()
methods in JavaScript? - How can you implement a debouncing function in JavaScript?
- What are generator functions in JavaScript and how can they be used?
- Explain the concept of the event loop and how it enables non-blocking I/O in JavaScript.
- How can you implement a memoization cache in JavaScript to optimize function calls?
- What are the differences between the
let
,const
, andclass
keywords in JavaScript? - Explain the concept of immutability in JavaScript and its benefits.
- How can you implement a custom iterator in JavaScript?
- What is the purpose of the
Promise.all()
method in JavaScript and how does it work? - Explain the differences between the
map()
,reduce()
, andfilter()
methods in JavaScript arrays. - How can you handle exceptions and errors in asynchronous JavaScript code?
- Explain the concept of event-driven programming and how it is implemented in JavaScript.
- What is the purpose of the
Symbol
data type in JavaScript and how can it be used? - How can you implement method chaining in JavaScript?
- Explain the concept of a proxy object in JavaScript and its applications.
- What are the differences between arrow functions and regular functions in JavaScript?
- How can you implement a publish-subscribe pattern in JavaScript?
- Explain the differences between shallow cloning and deep cloning of objects in JavaScript.
- What are the differences between a for loop and forEach loop in JavaScript? When should each be used?
- How can you create a private method in a JavaScript class?
- Explain the concept of lazy evaluation and how it can be achieved in JavaScript.
- What are the differences between the spread operator (
...
) and the rest parameter in JavaScript? - How can you implement method overriding in JavaScript?
- Explain the concept of currying and partial application in JavaScript.
- What is the purpose of the
Array.from()
method in JavaScript and how can it be used? - How can you implement a binary search algorithm in JavaScript?
Conclusion:
By exploring these 100 tricky JavaScript questions, you have delved into the depths of the language and expanded your coding expertise.
JavaScript’s versatility and wide adoption make it a valuable skill for any developer. Remember, mastering JavaScript requires continuous learning, practice, and experimentation.
With a strong foundation in the language and the ability to tackle challenging questions, you are well-equipped to excel in your JavaScript development journey. Keep exploring, stay curious, and never stop learning. Happy coding!