JavaScript Complete Sheet

Basic JavaScript Questions:

1. What is JavaScript and why is it used?
2. How do you include JavaScript in an HTML file?
3. What are the different data types in JavaScript?
4. What is the difference between var, let, and const?
5. Explain the concept of hoisting in JavaScript.
6. What are JavaScript functions? How do you declare a function?
7. What is the difference between function declarations and function expressions?
8. How do you create and use an array in JavaScript?
9. What are objects in JavaScript? How do you create and use them?
10. What are JavaScript events? Give examples.
11. How do you use if, else if, and else statements in JavaScript?
12. What is the difference between == and ===?
13. How do you use a for loop in JavaScript?
14. What is a while loop and how does it work?
15. How do you use the forEach method in JavaScript arrays?
16. What is a callback function? Provide an example.
17. How do you handle errors in JavaScript using try, catch, and finally?
18. What is the this keyword in JavaScript?
19. Explain the concept of closures in JavaScript.
20. What are template literals and how do you use them?

Intermediate JavaScript Questions:

21. What is the Document Object Model (DOM)?
22. How do you manipulate the DOM using JavaScript?
23. What are JavaScript promises and how do they work?
24. Explain the concept of async and await in JavaScript.
25. How do you handle asynchronous operations in JavaScript?
26. What is the difference between null and undefined?
27. How do you create and use a JavaScript class?
28. What is prototypal inheritance in JavaScript?
29. How do you use the map, filter, and reduce methods in JavaScript arrays?
30. What are JavaScript modules and how do you use them?
31. How do you create a module using export and import?
32. What is the Event Loop in JavaScript?
33. How does JavaScript handle concurrency with the Event Loop?
34. Explain the concept of strict mode in JavaScript.
35. What are higher-order functions in JavaScript?
36. How do you debounce and throttle functions in JavaScript?
37. What is the Fetch API and how do you use it?
38. How do you use localStorage and sessionStorage in JavaScript?
39. What are JavaScript Regular Expressions and how do you use them?
40. How do you use the spread operator in JavaScript?

Advanced JavaScript Questions:

41. What is context in JavaScript?
42. How do you bind a function to a specific context using bind, call, and apply?
43. What are generators in JavaScript and how do they work?
44. Explain the concept of Symbol in JavaScript.
45. What is Proxy in JavaScript and how do you use it?
46. How do you use Reflect in JavaScript?
47. What is the difference between synchronous and asynchronous code?
48. How do you handle deep cloning of objects in JavaScript?
49. What are Sets and Maps in JavaScript and how do you use them?
50. What are weak references in JavaScript and when would you use them?
51. How do you use async iterators and generators in JavaScript?
52. What is memoization and how do you implement it in JavaScript?
53. How do you implement a Singleton pattern in JavaScript?
54. What are Web Workers and how do you use them?
55. What is the purpose of Service Workers in JavaScript?
56. How do you create and handle custom events in JavaScript?
57. What is the difference between apply and spread operator?
58. Explain the concept of event delegation.
59. What are the different ways to clone an object in JavaScript?
60. What is the purpose of the WeakMap and WeakSet in JavaScript?

Expert JavaScript Questions:

61. Explain the concept of currying in JavaScript.
62. What is the Revealing Module Pattern in JavaScript?
63. How do you implement the Observer pattern in JavaScript?
64. What are TypeScript and its benefits over JavaScript?
65. How do you handle immutability in JavaScript?
66. What are JavaScript decorators and how do you use them?
67. How do you use Promise.all, Promise.race, Promise.allSettled, and Promise.any?
68. How do you manage state in a JavaScript application?
69. What is the concept of Virtual DOM in JavaScript frameworks?
70. How do you optimize performance in JavaScript applications?

JavaScript Best Practices and Performance:

71. What are the best practices for writing clean and maintainable JavaScript code?
72. How do you handle memory leaks in JavaScript?
73. What are the best practices for error handling in JavaScript?
74. How do you optimize JavaScript code for better performance?
75. What are the common security issues in JavaScript and how do you prevent them?
76. How do you manage dependencies in JavaScript projects?
77. What are the best practices for writing asynchronous JavaScript code?
78. How do you use ESLint to enforce coding standards in JavaScript?
79. What are some common JavaScript debugging techniques?
80. How do you write unit tests for JavaScript code?

JavaScript Tools and Frameworks:

81. What is Node.js and how does it differ from browser JavaScript?
82. How do you use npm (Node Package Manager)?
83. What are JavaScript build tools like Webpack, and how do you use them?
84. What is Babel and why is it used in JavaScript projects?
85. How do you use TypeScript with JavaScript projects?
86. What are JavaScript frameworks like React, Vue, and Angular?
87. How do you manage state in a React application?
88. What is the Vue.js reactivity system and how does it work?
89. How do you use Angular services and dependency injection?
90. What is Redux and how do you use it in JavaScript applications?

JavaScript Libraries and APIs:

91. What is jQuery and how is it used in JavaScript projects?
92. How do you use Lodash in JavaScript projects?
93. What are some popular JavaScript charting libraries and how do you use them?
94. How do you work with the Canvas API in JavaScript?
95. What is the Web Storage API and how do you use it?
96. How do you use the Geolocation API in JavaScript?
97. What is the Fetch API and how does it differ from XMLHttpRequest?
98. How do you use the WebRTC API for real-time communication in JavaScript?
99. What are Web Components and how do you create them?
100. How do you use the Intersection Observer API in JavaScript?

These questions cover a wide range of JavaScript topics, from basic syntax and concepts to advanced techniques and best practices, providing a comprehensive study resource.