1 . Can I redeclare let and const variables?
2 . Difference between Function Scope vs Block Scope in JavaScript?
3 . Difference between Local and Global Variable ?
4 . Difference between var and let in JavaScript?
5 . How garbage collection works in JavaScript ?
6 . List down some of the features of ES6 ?
7 . What are global variables ?
8 . What are namespaces?
9 . What are PWAs used for?
10 . What are raw strings?
11 . What are some unique features of JavaScript ?
12 . What are the benefit of event delegation?
13 . What does dynamic mean in JavaScript?
14 . What does it mean that JavaScript is "dynamic"?
15 . What is ES6 ?
16 . what is function declaration and function expression ?
17 . What is Hoisting ?
18 . What is JavaScript?
19 . What is polyfill used for?
20 . What is scope of variable in JavaScript ?
21 . What is shallow copied in javascript?
22 . What is Stack overflow in Javascript?
23 . What is the aim of the let keyword?
24 . What is the Call Stack in JavaScript ?
25 . What is the creation phase and execution phase in Javascript?
26 . What is the difference between DOM and BOM?
27 . What is the difference between java and javascript
28 . What is the difference between Shallow and Deep copy
29 . What is the Temporal Dead Zone (TDZ) in JavaScript?
30 . What is use strict mode?
31 . What paradigm is Javascript ?
32 . when does document load get executed?
33 . when does DOMContentLoaded get executed?
34 . Why should we use ES6 classes?
35 . How do you load CSS and JS files dynamically ?
36 . How do you run multiple promises together?
37 . Polyfill promise.all function in js ?
38 . What are the 3 states of promise?
39 . How to Scoping variables in JavaScript switch statement?
40 . What are falsy values in JavaScript?
41 . What is strict mode?
42 . What is the purpose of the finally?
43 . What is the use of break and continue statement in JavaScript?
44 . Differences between for(..in) and for(..of) statement in JavaScript?
45 . How do you create an infinite loop?
46 . What is for...of statement
47 . What is the difference between ( for... in ) and ( for... of ) statements?
48 . Why we use do while loop in JavaScript?
49 . What is the first-class function in Javascript?
50 . How do higher order functions work ?
51 . How to Use the Call, Apply, and Bind ?
52 . What are default values in the destructuring assignments?
53 . What are Events in JavaScript?
54 . What does the isNaN () function?
55 . What is a arrow function in JavaScript?
56 . What is a pure function ?
57 . What is a rest parameter ?
58 . what is arrow function?
59 . What is currying function in JavaScript ?
60 . What is destructuring assignment ?
61 . What is eval used for ?
62 . What is function default parameters?
63 . What is function rest parameters?
64 . What is IIFE(Immediately Invoked Function Expression) ?
65 . What is memoization ?
66 . What is recursion and why it is used?
67 . What is the arguments object?
68 . What is the purpose of setTimeout() function in JavaScript ?
69 . What is the use of preventDefault method
70 . What is throttling?
71 . When closures are created in JavaScript ?
72 . Where is anonymous function used?
73 . Why callback function is used?
74 . Difference Between undefined and null ?
75 . Difference TypeError and ReferenceError ?
76 . How in operator works in javascript ?
77 . How to delete an object property ?
78 . What does "!--" do in JavaScript?
79 . What is a debugger statement?
80 . What is == and === in JavaScript?
81 . What is assignment expression ?
82 . What is destructuring assignment?
83 . What is immutability?
84 . What is NaN property?
85 . What is nullish assignment?
86 . What is the ternary operator ?
87 . What undefined property indicates?
88 . What’s the double exclamation sign for in JavaScript?
89 . Generate Random Number between 1 and 10 ?
90 . How do you check a value is a number?
91 . How do you find the minimum and the maximum number of the array of numbers?
92 . How do you find the absolute value of a number?
93 . How to avoid scientific notation for large numbers in JavaScript?
94 . What is BigInt?
95 . What uses parseFloat and parseInt?
96 . How can repeat a string n times?
97 . How can we remove whitespace from a string?
98 . How do you make string first letter capitalized?
99 . How do you replace a specific part of a string?
100 . How to check a word in exists on a string?
101 . What are tagged templates ?
102 . What is the difference between staring startWith and starting endWith methods?
103 . when we should use regular expressions?
104 . Differences between Objects and Maps ?
105 . How can we check a value is a Array or not?
106 . How can we concatenated nested arrays?
107 . How do you check whether an array includes a particular value or not
108 . How to check whether there is a specific value in the Array?
109 . How we can merge nested arrays in javascript?
110 . What is the purpose of Array reduce method?
111 . What is the purpose of some method in arrays ?
112 . What is the purpose of the array slice method ?
113 . What is the use case of array concat method?
114 . Deference between Array and Set in javascript?
115 . What is difference between Map and Object?
116 . What is Map object?
117 . What is the purpose of the Set in javascript?
118 . Difference between getOwnPropertyNames vs Object.keys ?
119 . How can access an object's values?
120 . How can we set an object's prototype in JavaScript ?
121 . How do you get objects all prototypes ?
122 . How do you get property descriptors of an object
123 . How Prototype inheretated with Object.create() ?
124 . What is Optional chaining ?
125 . What happens if you define a property in an object, when a property with the same name is defined in the object's prototype?
126 . What is prototype chain ?
127 . What is constructor function?
128 . What is getter and setter in javascript?
129 . What is Object.assign() do ?
130 . What is object in javascript?
131 . What is Object property descriptor?
132 . How can we define a private method in the javascript class?
133 . How do we set a property or method private in javascript?
134 . Is Class Declaration hoisted to the top?
135 . What is a constructor method
136 . What is Abstraction in OOP ?
137 . What is class in javascript?
138 . What is Encapsulation in JavaScript?
139 . What is static method in javascript?
140 . What are the 4 pillars of OOP?
141 . Is it possible to chain promises after getting an Error?
142 . What are the cons of promises?
143 . What does promise all do?
144 . What is a promise?
145 . What is a promise.race() ?
146 . What is Polymorphism in JavaScript ?
147 . What is promise chaining give an example?
148 . What promise chaining ?
149 . What is iterable?
150 . What is purpose of proxies in javascript?
151 . Difference between default export and named export ?
152 . What are dynamic imports?
153 . What is defer in javascript?
154 . What is type="module" in the <script> tag?
155 . How can we communicate between two different tabs?
156 . How do I modify the url without reloading the page
157 . How to access DOM from web worker?
158 . How to get a specific query param value from an URL?
159 . What are server-sent events?
160 . What is cookies ?
161 . What is IndexedDB used for?
162 . What is Service Worker ?
163 . What is the use case of session storage in the web application?
164 . What is web storage?
165 . Why do we use setInterval in JavaScript?
166 . Why do we use web workers?
167 . What are closures?
168 . What are closures scope chains?
169 . How does a web browser work
170 . Implement Array at polyfill ?
171 . Implement Array concat polyfill ?
172 . Implement Array copywithin polyfill ?
173 . Implement Array every polyfill ?
174 . Implement Array fill polyfill ?
175 . Implement Array filter polyfill ?
176 . Implement Array find polyfill ?
177 . Implement Array forEach polyfill ?
178 . Implement Array includes polyfill ?
179 . Implement Array indexOf polyfill ?
180 . Implement Array join polyfill ?
181 . Implement Array map polyfill ?
182 . Implement Array slice polyfill ?
183 . Implement Array some polyfill ?
184 . Implement Array unshift polyfill ?
185 . Implement stack data structure ?
186 . What is the output of below code
187 . What is the output of below code
188 . What will the following code output to the console and why?
189 . Consider the following code. What will the output be, and why?
190 . What will be the output of this code?
191 . How do you add an element at the begining of an array? How do you add one at the end?
192 . What is the value of typeof undefined == typeof NULL?
193 . What would following code return?
194 . What will the following code output and why?
195 . What is the output of below code ?
196 . What is the output of below code ?
197 . What's the output?
198 . What's the output?