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1. How do null and undefined differ in terms of their behavior in JavaScript?
easy 2. What is type coercion in JavaScript and how does it work?
easy 3. What is the purpose of using both `==` and `===` operators in JavaScript, and when would you use one over the other?
easy 4. In JavaScript, what is hoisting and how does it impact the way variables and functions are declared and used?
easy 5. What is closure in JavaScript and how does it work? Provide an example.
easy 6. How does the "this" keyword work in JavaScript, explain with the help of examples and what are some common pitfalls to be aware of when using it?
hard 7. How does JavaScript define the scope of variables? Explain with the help of an example.
medium 8. Can you explain what arrow functions are in JavaScript and how they differ from regular functions?
medium 9. Can you explain how higher-order functions work in JavaScript and give a suitable example to support your explanation?
medium 10. How does an IIFE work in JavaScript, and why would you use it? Also provide an example
hard 11. What is functional programming and how does its concepts apply in JavaScript? Also provide an example
medium 12. In JavaScript are functions treated as first class object? If yes then explain with the help of an example.
medium 13. Can you explain the different ways to create objects in JavaScript, including object literals, constructor functions, and prototypal inheritance?
easy 14. Can you explain the different data types available in JavaScript and their characteristics?
easy 15. Can you explain how the event loop works in JavaScript and what it does?
hard 16. Can you explain the concept of callbacks in JavaScript? Also provide an example to support your explanation.
medium 17. How do callbacks differ from other synchronous constructs like functions or loops in JavaScript, and why are they preferred in certain situations?
hard 18. Can you provide an explanation of callback hell in JavaScript, including some common scenarios where it may occur and possible solutions to address it?
hard 19. What is a promise in JavaScript and how does it work?
hard 20. How do you chain multiple Promises together in JavaScript, and what benefits does this offer?
medium 21. What are Promise.all and Promise.race methods in JavaScript? When would you prefer to use one over the other?
medium 22. What is the difference between Promise.all and Promise.allSettled in JavaScript?
hard 23. What is the difference between Promise.any and Promise.race in JavaScript?
hard 24. What are the pros and cons of promises over callbacks?
medium 25. What are the different error handling patterns that can be used for error handling with promises?
medium 26. Explain the concept of prototypal inheritance in JavaScript.
medium 27. Can you provide an example to illustrate the differences between `proto` and `prototype` in JavaScript, including how they are used and what they do?
hard 28. What is the difference between object literals and constructor functions?
easy 29. Explain the concept of async/await and how it simplifies asynchronous programming in JavaScript. How does it differ from using promises?
medium 30. Can you explain what the job queue or microtask queue is in JavaScript and how it works?
hard 31. How do you create private variables in JavaScript?
medium 32. Discuss the differences between event propagation and event bubbling in the DOM.
medium 33. How can you access and manipulate the browser history in JavaScript?
easy 34. Explain the usage of let and const keywords in JavaScript.
easy 35. What is destructuring assignment in JavaScript?
easy 36. What are modules in ES6?
medium 37. Explain the concept of 'this' keyword in JavaScript. Also, how does it work inside of the event handlers?
hard 38. What is the difference between event.preventDefault() and event.stopPropagation() methods in JavaScript?
medium 39. What is event delegation in JavaScript? What are the various scenarios in which it is useful?
medium 40. What is the difference between localStorage, sessionStorage and cookies in JavaScript? Explain with the help of examples when would you prefer to use one over the other?
medium 41. What is Cross-Origin Resource Sharing (CORS) and how do you handle it in JavaScript?
hard 42. What is Cross-Site Scripting (XSS) and how can we prevent it?
hard 43. What is Content Security Policy (CSP)? How can it help in preventing web security attacks?
medium 44. What are template literals in JavaScript? Can they be used for string interpolation?
easy 45. How do you perform exception handling in JavaScript?
medium 46. What are the various error handling statements used in JavaScript?
medium 47. Explain the concept of breakpoints in debugging a JavaScript program.
medium 48. What are the various methods to access DOM elements in JavaScript?
easy 49. What are event listeners in JavaScript? How can we add and remove one from an element?
easy 50. What is the difference between the call, apply and bind methods in JavaScript?
easy 51. What is a higher order function? Explain with the help of relevant examples.
easy 52. What is function currying? Explain with the help of an example.
medium 53. What is URL encoding? How can we encode or decode a URL in JavaScript?
easy 54. What is a pure function? Explain with the help of an example in JavaScript.
easy 55. What is a first order function? Explain with the help of an example in JavaScript.
easy 56. Discuss the importance of web page loading time and performance.
medium 57. Are functions treated as first class objects in JavaScript? Support your answer with the help of an example in either case.
medium 58. What is a unary function? Explain with the help of an example.
easy 59. What is memoization in functional programming? Explain with the help of an example in JavaScript.
medium 60. What are async iterators and generators in JavaScript?
hard 61. What are dynamic imports in JavaScript?
hard 62. Can you explain the difference between the usage of Object.entries() and Object.values()?
easy 63. How does JavaScript handle big integers (BigInt)?
medium 64. What is the Document Object Model (DOM) in JavaScript?
medium 65. What is the difference between document load and DOMContentLoaded events in JavaScript?
medium 66. What are the differences between the window and the document object in JavaScript?
medium 67. What is a service worker in JavaScript?
medium 68. How can we reuse information across service worker restarts in JavaScript?
medium 69. What are the differences between the arrow functions and the regular functions in JavaScript?
hard 70. Explain about the post message method in JavaScript? Also mention its utilities and restrictions.
medium 71. What are server-sent events?
medium 72. How do you ensure that your JavaScript code is cross-browser compatible?
medium 73. What is Babel and how is it used in JavaScript development?
medium 74. What are module bundlers and what is their role in modern JavaScript development?
medium 75. What is tree shaking in module bundling?
medium 76. What are classes in ES6?
easy 77. What is the use of JSON.stringify() method?
easy 78. How do you redirect to a new page programmatically in JavaScript?
easy 79. What are setTimeout and setInterval timing functions in JavaScript?
easy 80. What is a cookie in JavaScript?
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