A
1 React Interview Questions
2 Core React
3 What is React?
4 React All Hooks and its uses
5 lifecycle methods
6 What is props
7 function Component vs Class Component
8 package.json use?
9 Node-modules
10 What is manifest file use
11 one way data binding?
12 Higher order component (HOC)
13 stateless and Statefull component
14 State Lifting?
15 Memonization?
16 Protected Routes?
17 Custom Hook?
18 Exicution Context?
19 Error Handling in React?
20 What are the major features of React?
21 What is JSX?
22 What is the difference between Element and Component?
23 How to create components in React?
24 When to use a Class Component over a Function Component?
25 What are Pure Components?
26 What is state in React?
27 What are props in React?
28 What is the difference between state and props?
29 Why should we not update the state directly?
30 What is the purpose of callback function as an argument of setState()?
31 What is the difference between HTML and React event handling?
32 How to bind methods or event handlers in JSX callbacks?
33 How to pass a parameter to an event handler or callback?
34 What are synthetic events in React?
35 What are inline conditional expressions?
36 What is "key" prop and what is the benefit of using it in arrays of elements?
37 What is the use of refs?
38 How to create refs?
39 What are forward refs?
40 Which is preferred option with in callback refs and findDOMNode()?
41 Why are String Refs legacy?
42 What is Virtual DOM?
43 How Virtual DOM works?
44 What is the difference between Shadow DOM and Virtual DOM?
45 What is React Fiber?
46 What is the main goal of React Fiber?
47 What are controlled components?
48 What are uncontrolled components?
49 What is the difference between createElement and cloneElement?
50 What is Lifting State Up in React?
51 What are the different phases of component lifecycle?
52 What are the lifecycle methods of React?
53 What are Higher-Order components?
54 How to create props proxy for HOC component?
55 What is context?
56 What is children prop?
57 How to write comments in React?
58 What is the purpose of using super constructor with props argument?

|  | A |
|  | - |
| 1 | React Interview Questions |
| 2 | Core React |
| 3 | What is React? |
| 4 | React All Hooks and its uses |
| 5 | lifecycle methods |
| 6 | What is props |
| 7 | function Component vs Class Component |
| 8 | package.json use? |
| 9 | Node-modules |
| 10 | What is manifest file use |
| 11 | one way data binding? |
| 12 | Higher order component (HOC) |
| 13 | stateless and Statefull component |
| 14 | State Lifting? |
| 15 | Memonization? |
| 16 | Protected Routes? |
| 17 | Custom Hook? |
| 18 | Exicution Context? |
| 19 | Error Handling in React? |
| 20 | What are the major features of React? |
| 21 | What is JSX? |
| 22 | What is the difference between Element and Component? |
| 23 | How to create components in React? |
| 24 | When to use a Class Component over a Function Component? |
| 25 | What are Pure Components? |
| 26 | What is state in React? |
| 27 | What are props in React? |
| 28 | What is the difference between state and props? |
| 29 | Why should we not update the state directly? |
| 30 | What is the purpose of callback function as an argument of setState()? |
| 31 | What is the difference between HTML and React event handling? |
| 32 | How to bind methods or event handlers in JSX callbacks? |
| 33 | How to pass a parameter to an event handler or callback? |
| 34 | What are synthetic events in React? |
| 35 | What are inline conditional expressions? |
| 36 | What is "key" prop and what is the benefit of using it in arrays of elements? |
| 37 | What is the use of refs? |
| 38 | How to create refs? |
| 39 | What are forward refs? |
| 40 | Which is preferred option with in callback refs and findDOMNode()? |
| 41 | Why are String Refs legacy? |
| 42 | What is Virtual DOM? |
| 43 | How Virtual DOM works? |
| 44 | What is the difference between Shadow DOM and Virtual DOM? |
| 45 | What is React Fiber? |
| 46 | What is the main goal of React Fiber? |
| 47 | What are controlled components? |
| 48 | What are uncontrolled components? |
| 49 | What is the difference between createElement and cloneElement? |
| 50 | What is Lifting State Up in React? |
| 51 | What are the different phases of component lifecycle? |
| 52 | What are the lifecycle methods of React? |
| 53 | What are Higher-Order components? |
| 54 | How to create props proxy for HOC component? |
| 55 | What is context? |
| 56 | What is children prop? |
| 57 | How to write comments in React? |
| 58 | What is the purpose of using super constructor with props argument? |

A
59 What is reconciliation?
60 How to set state with a dynamic key name?
61 What would be the common mistake of function being called every time the component renders?
62 Is lazy function supports named exports?
63 Why React uses className over class attribute?
64 What are fragments?
65 Why fragments are better than container divs?
66 What are portals in React?
67 What are stateless components?
68 What are stateful components?
69 How to apply validation on props in React?
70 What are the advantages of React?
71 What are the limitations of React?
72 What are error boundaries in React v16
73 How are error boundaries handled in React v15?
74 What are the recommended ways for static type checking?
75 What is the use of react-dom package?
76 What is the purpose of render method of react-dom?
77 What is ReactDOMServer?
78 How to use InnerHtml in React?
79 How to use styles in React?
80 How events are different in React?
81 What will happen if you use setState in constructor?
82 What is the impact of indexes as keys?
83 Is it good to use setState() in componentWillMount() method?
84 What will happen if you use props in initial state?
85 How do you conditionally render components?
86 Why we need to be careful when spreading props on DOM elements??
87 How you use decorators in React?
88 How do you memoize a component?
89 How you implement Server-Side Rendering or SSR?
90 How to enable production mode in React?
91 What is CRA and its benefits?
92 What is the lifecycle methods order in mounting?
93 What are the lifecycle methods going to be deprecated in React v16?
94 What is the purpose of getDerivedStateFromProps() lifecycle method?
95 What is the purpose of getSnapshotBeforeUpdate() lifecycle method?
96 Do Hooks replace render props and higher order components?
97 What is the recommended way for naming components?
98 What is the recommended ordering of methods in component class?
99 What is a switching component?
100 Why we need to pass a function to setState()?
101 What is strict mode in React?
102 What are React Mixins?
103 Why is isMounted() an anti-pattern and what is the proper solution?
104 What are the Pointer Events supported in React?
105 Why should component names start with capital letter?
106 Are custom DOM attributes supported in React v16?
107 What is the difference between constructor and getInitialState?
108 Can you force a component to re-render without calling setState?
109 What is the difference between super() and super(props) in React using ES6 classes?
110 How do you access props in attribute quotes?
111 How to loop inside JSX?
112 What is React PropType array with shape?
113 How to conditionally apply class attributes?
114 What is the difference between React and ReactDOM?
115 How to use React label element?
116 How to combine multiple inline style objects?

|  | A |
|  | - |
| 59 | What is reconciliation? |
| 60 | How to set state with a dynamic key name? |
| 61 | What would be the common mistake of function being called every time the component renders? |
| 62 | Is lazy function supports named exports? |
| 63 | Why React uses className over class attribute? |
| 64 | What are fragments? |
| 65 | Why fragments are better than container divs? |
| 66 | What are portals in React? |
| 67 | What are stateless components? |
| 68 | What are stateful components? |
| 69 | How to apply validation on props in React? |
| 70 | What are the advantages of React? |
| 71 | What are the limitations of React? |
| 72 | What are error boundaries in React v16 |
| 73 | How are error boundaries handled in React v15? |
| 74 | What are the recommended ways for static type checking? |
| 75 | What is the use of react-dom package? |
| 76 | What is the purpose of render method of react-dom? |
| 77 | What is ReactDOMServer? |
| 78 | How to use InnerHtml in React? |
| 79 | How to use styles in React? |
| 80 | How events are different in React? |
| 81 | What will happen if you use setState in constructor? |
| 82 | What is the impact of indexes as keys? |
| 83 | Is it good to use setState() in componentWillMount() method? |
| 84 | What will happen if you use props in initial state? |
| 85 | How do you conditionally render components? |
| 86 | Why we need to be careful when spreading props on DOM elements?? |
| 87 | How you use decorators in React? |
| 88 | How do you memoize a component? |
| 89 | How you implement Server-Side Rendering or SSR? |
| 90 | How to enable production mode in React? |
| 91 | What is CRA and its benefits? |
| 92 | What is the lifecycle methods order in mounting? |
| 93 | What are the lifecycle methods going to be deprecated in React v16? |
| 94 | What is the purpose of getDerivedStateFromProps() lifecycle method? |
| 95 | What is the purpose of getSnapshotBeforeUpdate() lifecycle method? |
| 96 | Do Hooks replace render props and higher order components? |
| 97 | What is the recommended way for naming components? |
| 98 | What is the recommended ordering of methods in component class? |
| 99 | What is a switching component? |
| 100 | Why we need to pass a function to setState()? |
| 101 | What is strict mode in React? |
| 102 | What are React Mixins? |
| 103 | Why is isMounted() an anti-pattern and what is the proper solution? |
| 104 | What are the Pointer Events supported in React? |
| 105 | Why should component names start with capital letter? |
| 106 | Are custom DOM attributes supported in React v16? |
| 107 | What is the difference between constructor and getInitialState? |
| 108 | Can you force a component to re-render without calling setState? |
| 109 | What is the difference between super() and super(props) in React using ES6 classes? |
| 110 | How do you access props in attribute quotes? |
| 111 | How to loop inside JSX? |
| 112 | What is React PropType array with shape? |
| 113 | How to conditionally apply class attributes? |
| 114 | What is the difference between React and ReactDOM? |
| 115 | How to use React label element? |
| 116 | How to combine multiple inline style objects? |

A
117 How to re-render the view when the browser is resized?
118 What is the difference between setState and replaceState methods?
119 How to listen to state changes?
120 What is the recommended approach of removing an array element in react state?
121 Is it possible to use React without rendering HTML?
122 How to pretty print JSON with React?
123 Why you can't update props in React?
124 How to focus an input element on page load?
125 What are the possible ways of updating objects in state?
126 How can we find the version of React at runtime in the browser?
127 What are the approaches to include polyfills in your create-react-app?
128 How to use https instead of http in create-react-app?
129 How to avoid using relative path imports in create-react-app?
130 How to add Google Analytics for react-router?
131 How to update a component every second?
132 How do you apply vendor prefixes to inline styles in React?
133 How to import and export components using react and ES6?
134 What are the exceptions on React component naming?
135 Why is a component constructor called only once?
136 How to define constants in React?
137 How to programmatically trigger click event in React?
138 Is it possible to use async/await in plain React?
139 What are the common folder structures for React?
140 What are the popular packages for animation?
141 What is the benefit of styles modules?
142 What are the popular React-specific linters?
143 How to make AJAX call and In which component lifecycle methods should I make an AJAX call?
144 What are render props?
145 React Router
146 What is React Router?
147 How React Router is different from history library?
148 What are the <Router> components of React Router v4?
149 What is the purpose of push and replace methods of history?
150 How do you programmatically navigate using React router v4?
151 How to get query parameters in React Router v4
152 Why you get "Router may have only one child element" warning?
153 How to pass params to history.push method in React Router v4?
154 How to implement default or NotFound page?
155 How to get history on React Router v4?
156 How to perform automatic redirect after login?
157 React Internationalization
158 What is React-Intl?
159 What are the main features of React Intl?
160 What are the two ways of formatting in React Intl?
161 How to use FormattedMessage as placeholder using React Intl?
162 How to access current locale with React Intl
163 How to format date using React Intl?
164 React Testing
165 What is Shallow Renderer in React testing?
166 What is TestRenderer package in React?
167 What is the purpose of ReactTestUtils package?
168 What is Jest?
169 What are the advantages of Jest over Jasmine?
170 Give a simple example of Jest test case
171 React Redux
172 What is Flux?
173 What is Redux?
174 What are the core principles of Redux?

|  | A |
|  | - |
| 117 | How to re-render the view when the browser is resized? |
| 118 | What is the difference between setState and replaceState methods? |
| 119 | How to listen to state changes? |
| 120 | What is the recommended approach of removing an array element in react state? |
| 121 | Is it possible to use React without rendering HTML? |
| 122 | How to pretty print JSON with React? |
| 123 | Why you can't update props in React? |
| 124 | How to focus an input element on page load? |
| 125 | What are the possible ways of updating objects in state? |
| 126 | How can we find the version of React at runtime in the browser? |
| 127 | What are the approaches to include polyfills in your create-react-app? |
| 128 | How to use https instead of http in create-react-app? |
| 129 | How to avoid using relative path imports in create-react-app? |
| 130 | How to add Google Analytics for react-router? |
| 131 | How to update a component every second? |
| 132 | How do you apply vendor prefixes to inline styles in React? |
| 133 | How to import and export components using react and ES6? |
| 134 | What are the exceptions on React component naming? |
| 135 | Why is a component constructor called only once? |
| 136 | How to define constants in React? |
| 137 | How to programmatically trigger click event in React? |
| 138 | Is it possible to use async/await in plain React? |
| 139 | What are the common folder structures for React? |
| 140 | What are the popular packages for animation? |
| 141 | What is the benefit of styles modules? |
| 142 | What are the popular React-specific linters? |
| 143 | How to make AJAX call and In which component lifecycle methods should I make an AJAX call? |
| 144 | What are render props? |
| 145 | React Router |
| 146 | What is React Router? |
| 147 | How React Router is different from history library? |
| 148 | What are the <Router> components of React Router v4? |
| 149 | What is the purpose of push and replace methods of history? |
| 150 | How do you programmatically navigate using React router v4? |
| 151 | How to get query parameters in React Router v4 |
| 152 | Why you get "Router may have only one child element" warning? |
| 153 | How to pass params to history.push method in React Router v4? |
| 154 | How to implement default or NotFound page? |
| 155 | How to get history on React Router v4? |
| 156 | How to perform automatic redirect after login? |
| 157 | React Internationalization |
| 158 | What is React-Intl? |
| 159 | What are the main features of React Intl? |
| 160 | What are the two ways of formatting in React Intl? |
| 161 | How to use FormattedMessage as placeholder using React Intl? |
| 162 | How to access current locale with React Intl |
| 163 | How to format date using React Intl? |
| 164 | React Testing |
| 165 | What is Shallow Renderer in React testing? |
| 166 | What is TestRenderer package in React? |
| 167 | What is the purpose of ReactTestUtils package? |
| 168 | What is Jest? |
| 169 | What are the advantages of Jest over Jasmine? |
| 170 | Give a simple example of Jest test case |
| 171 | React Redux |
| 172 | What is Flux? |
| 173 | What is Redux? |
| 174 | What are the core principles of Redux? |

A
175 What are the downsides of Redux compared to Flux?
176 What is the difference between mapStateToProps() and mapDispatchToProps()?
177 Can I dispatch an action in reducer?
178 How to access Redux store outside a component?
179 What are the drawbacks of MVW pattern
180 Are there any similarities between Redux and RxJS?
181 How to dispatch an action on load?
182 How to use connect from React Redux?
183 How to reset state in Redux?
184 Whats the purpose of at symbol in the redux connect decorator?
185 What is the difference between React context and React Redux?
186 Why are Redux state functions called reducers?
187 How to make AJAX request in Redux?
188 Should I keep all component's state in Redux store?
189 What is the proper way to access Redux store?
190 What is the difference between component and container in React Redux?
191 What is the purpose of the constants in Redux?
192 What are the different ways to write mapDispatchToProps()?
193 What is the use of the ownProps parameter in mapStateToProps() and mapDispatchToProps()?
194 How to structure Redux top level directories?
195 What is redux-saga?
196 What is the mental model of redux-saga?
197 What are the differences between call and put in redux-saga
198 What is Redux Thunk?
199 What are the differences between redux-saga and redux-thunk
200 What is Redux DevTools?
201 What are the features of Redux DevTools?
202 What are Redux selectors and Why to use them?
203 What is Redux Form?
204 What are the main features of Redux Form?
205 How to add multiple middlewares to Redux?
206 How to set initial state in Redux?
207 How Relay is different from Redux?
208 What is an action in Redux?
209 What is React Native
210 What is the difference between React Native and React?
211 How to test React Native apps?
212 How to do logging in React Native?
213 How to debug your React Native?
214 React supported libraries and Integration
215 What is reselect and how it works?
216 What is Flow?
217 What is the difference between Flow and PropTypes?
218 How to use font-awesome icons in React?
219 What is React Dev Tools?
220 Why is DevTools not loading in Chrome for local files?
221 How to use Polymer in React?
222 What are the advantages of React over Vue.js?
223 What is the difference between React and Angular?
224 Why React tab is not showing up in DevTools?
225 What are styled components?
226 Give an example of Styled Components?
227 What is Relause TypeScript in create-react-app application?
228 Miscellaneous
229 What are the main features of reselect library?
230 Give an example of reselect usage?
231 Does the statics object work with ES6 classes in React?
232 Can Redux only be used with React?

|  | A |
|  | - |
| 175 | What are the downsides of Redux compared to Flux? |
| 176 | What is the difference between mapStateToProps() and mapDispatchToProps()? |
| 177 | Can I dispatch an action in reducer? |
| 178 | How to access Redux store outside a component? |
| 179 | What are the drawbacks of MVW pattern |
| 180 | Are there any similarities between Redux and RxJS? |
| 181 | How to dispatch an action on load? |
| 182 | How to use connect from React Redux? |
| 183 | How to reset state in Redux? |
| 184 | Whats the purpose of at symbol in the redux connect decorator? |
| 185 | What is the difference between React context and React Redux? |
| 186 | Why are Redux state functions called reducers? |
| 187 | How to make AJAX request in Redux? |
| 188 | Should I keep all component's state in Redux store? |
| 189 | What is the proper way to access Redux store? |
| 190 | What is the difference between component and container in React Redux? |
| 191 | What is the purpose of the constants in Redux? |
| 192 | What are the different ways to write mapDispatchToProps()? |
| 193 | What is the use of the ownProps parameter in mapStateToProps() and mapDispatchToProps()? |
| 194 | How to structure Redux top level directories? |
| 195 | What is redux-saga? |
| 196 | What is the mental model of redux-saga? |
| 197 | What are the differences between call and put in redux-saga |
| 198 | What is Redux Thunk? |
| 199 | What are the differences between redux-saga and redux-thunk |
| 200 | What is Redux DevTools? |
| 201 | What are the features of Redux DevTools? |
| 202 | What are Redux selectors and Why to use them? |
| 203 | What is Redux Form? |
| 204 | What are the main features of Redux Form? |
| 205 | How to add multiple middlewares to Redux? |
| 206 | How to set initial state in Redux? |
| 207 | How Relay is different from Redux? |
| 208 | What is an action in Redux? |
| 209 | What is React Native |
| 210 | What is the difference between React Native and React? |
| 211 | How to test React Native apps? |
| 212 | How to do logging in React Native? |
| 213 | How to debug your React Native? |
| 214 | React supported libraries and Integration |
| 215 | What is reselect and how it works? |
| 216 | What is Flow? |
| 217 | What is the difference between Flow and PropTypes? |
| 218 | How to use font-awesome icons in React? |
| 219 | What is React Dev Tools? |
| 220 | Why is DevTools not loading in Chrome for local files? |
| 221 | How to use Polymer in React? |
| 222 | What are the advantages of React over Vue.js? |
| 223 | What is the difference between React and Angular? |
| 224 | Why React tab is not showing up in DevTools? |
| 225 | What are styled components? |
| 226 | Give an example of Styled Components? |
| 227 | What is Relause TypeScript in create-react-app application? |
| 228 | Miscellaneous |
| 229 | What are the main features of reselect library? |
| 230 | Give an example of reselect usage? |
| 231 | Does the statics object work with ES6 classes in React? |
| 232 | Can Redux only be used with React? |

A
233 Do you need to have a particular build tool to use Redux?
234 How Redux Form initialValues get updated from state?
235 How React PropTypes allow different type for one prop?
236 Can I import an SVG file as react component?
237 Why are inline ref callbacks or functions not recommended?
238 What is render hijacking in React?
239 What are HOC factory implementations?
240 How to pass numbers to React component?
241 Do I need to keep all my state into Redux? Should I ever use react internal state?
242 What is the purpose of registerServiceWorker in React?
243 What is React memo function?
244 What is React lazy function?
245 How to prevent unnecessary updates using setState?
246 How do you render Array, Strings and Numbers in React 16 Version?
247 How to use class field declarations syntax in React classes?
248 What are hooks?
249 What rules need to be followed for hooks?
250 How to ensure hooks followed the rules in your project?
251 What are the differences between Flux and Redux?
252 What are the benefits of React Router V4?
253 Can you describe about componentDidCatch lifecycle method signature?
254 In which scenarios error boundaries do not catch errors?
255 Why do you not need error boundaries for event handlers?
256 What is the difference between try catch block and error boundaries?
257 What is the behavior of uncaught errors in react 16?
258 What is the proper placement for error boundaries?
259 What is the benefit of component stack trace from error boundary?
260 What is the required method to be defined for a class component?
261 What are the possible return types of render method?
262 What is the main purpose of constructor?
263 Is it mandatory to define constructor for React component?
264 What are default props?
265 Why should not call setState in componentWillUnmount?
266 What is the purpose of getDerivedStateFromError?
267 What is the methods order when component re-rendered?
268 What are the methods invoked during error handling?
269 What is the purpose of displayName class property?
270 What is the browser support for react applications?
271 What is the purpose of unmountComponentAtNode method?
272 What is code-splitting?
273 What is the benefit of strict mode?
274 What are Keyed Fragments?
275 Does React support all HTML attributes?
276 What are the limitations with HOCs?
277 How to debug forwardRefs in DevTools?
278 When component props defaults to true?
279 What is NextJS and major features of it?
280 How do you pass an event handler to a component?
281 Is it good to use arrow functions in render methods?
282 How to prevent a function from being called multiple times?
283 How JSX prevents Injection Attacks?
284 How do you update rendered elements?
285 How do you say that props are read only?
286 How do you say that state updates are merged?
287 How do you pass arguments to an event handler?
288 How to prevent component from rendering?
289 What are the conditions to safely use the index as a key?
290 Is it keys should be globally unique?

|  | A |
|  | - |
| 233 | Do you need to have a particular build tool to use Redux? |
| 234 | How Redux Form initialValues get updated from state? |
| 235 | How React PropTypes allow different type for one prop? |
| 236 | Can I import an SVG file as react component? |
| 237 | Why are inline ref callbacks or functions not recommended? |
| 238 | What is render hijacking in React? |
| 239 | What are HOC factory implementations? |
| 240 | How to pass numbers to React component? |
| 241 | Do I need to keep all my state into Redux? Should I ever use react internal state? |
| 242 | What is the purpose of registerServiceWorker in React? |
| 243 | What is React memo function? |
| 244 | What is React lazy function? |
| 245 | How to prevent unnecessary updates using setState? |
| 246 | How do you render Array, Strings and Numbers in React 16 Version? |
| 247 | How to use class field declarations syntax in React classes? |
| 248 | What are hooks? |
| 249 | What rules need to be followed for hooks? |
| 250 | How to ensure hooks followed the rules in your project? |
| 251 | What are the differences between Flux and Redux? |
| 252 | What are the benefits of React Router V4? |
| 253 | Can you describe about componentDidCatch lifecycle method signature? |
| 254 | In which scenarios error boundaries do not catch errors? |
| 255 | Why do you not need error boundaries for event handlers? |
| 256 | What is the difference between try catch block and error boundaries? |
| 257 | What is the behavior of uncaught errors in react 16? |
| 258 | What is the proper placement for error boundaries? |
| 259 | What is the benefit of component stack trace from error boundary? |
| 260 | What is the required method to be defined for a class component? |
| 261 | What are the possible return types of render method? |
| 262 | What is the main purpose of constructor? |
| 263 | Is it mandatory to define constructor for React component? |
| 264 | What are default props? |
| 265 | Why should not call setState in componentWillUnmount? |
| 266 | What is the purpose of getDerivedStateFromError? |
| 267 | What is the methods order when component re-rendered? |
| 268 | What are the methods invoked during error handling? |
| 269 | What is the purpose of displayName class property? |
| 270 | What is the browser support for react applications? |
| 271 | What is the purpose of unmountComponentAtNode method? |
| 272 | What is code-splitting? |
| 273 | What is the benefit of strict mode? |
| 274 | What are Keyed Fragments? |
| 275 | Does React support all HTML attributes? |
| 276 | What are the limitations with HOCs? |
| 277 | How to debug forwardRefs in DevTools? |
| 278 | When component props defaults to true? |
| 279 | What is NextJS and major features of it? |
| 280 | How do you pass an event handler to a component? |
| 281 | Is it good to use arrow functions in render methods? |
| 282 | How to prevent a function from being called multiple times? |
| 283 | How JSX prevents Injection Attacks? |
| 284 | How do you update rendered elements? |
| 285 | How do you say that props are read only? |
| 286 | How do you say that state updates are merged? |
| 287 | How do you pass arguments to an event handler? |
| 288 | How to prevent component from rendering? |
| 289 | What are the conditions to safely use the index as a key? |
| 290 | Is it keys should be globally unique? |

A
291 What is the popular choice for form handling?
292 What are the advantages of formik over redux form library?
293 Why do you not required to use inheritance?
294 Can I use web components in react application?
295 What is dynamic import?
296 What are loadable components?
297 What is suspense component?
298 What is route based code splitting?
299 Give an example on How to use context?
300 What is the purpose of default value in context?
301 How do you use contextType?
302 What is a consumer?
303 How do you solve performance corner cases while using context?
304 What is the purpose of forward ref in HOCs?
305 Is it ref argument available for all functions or class components?
306 Why do you need additional care for component libraries while using forward refs?
307 How to create react class components without ES6?
308 Is it possible to use react without JSX?
309 What is diffing algorithm?
310 What are the rules covered by diffing algorithm?
311 When do you need to use refs?
312 Is it prop must be named as render for render props?
313 What are the problems of using render props with pure components?
314 How do you create HOC using render props?
315 What is windowing technique?
316 How do you print falsy values in JSX?
317 What is the typical use case of portals?
318 How do you set default value for uncontrolled component?
319 What is your favorite React stack?
320 Why ReactDOM is separated from React?
321 What is the difference between Real DOM and Virtual DOM?
322 How to add Bootstrap to a react application?
323 Can you list down top websites or applications using react as front end framework?
324 Is it recommended to use CSS In JS technique in React?
325 Do I need to rewrite all my class components with hooks?
326 How to fetch data with React Hooks?
327 Is Hooks cover all use cases for classes?
328 What is the stable release for hooks support?
329 Why do we use array destructuring (square brackets notation) in useState?
330 What are the sources used for introducing hooks?
331 How do you access imperative API of web components?
332 What is formik?
333 What are typical middleware choices for handling asynchronous calls in Redux?
334 Do browsers understand JSX code?
335 Describe about data flow in react?
336 What is react scripts?
337 What are the features of create react app?
338 What is the purpose of renderToNodeStream method?
339 What is MobX?
340 What are the differences between Redux and MobX?
341 Should I learn ES6 before learning ReactJS?
342 What is Concurrent Rendering?
343 What is the difference between async mode and concurrent mode?
344 Can I use javascript urls in react16.9?
345 What is the purpose of eslint plugin for hooks?
346 What is the difference between Imperative and Declarative in React?
347 What are the benefits of using typescript with reactjs?
348 How do you make sure that user remains authenticated on page refresh while using Context API State Management?

|  | A |
|  | - |
| 291 | What is the popular choice for form handling? |
| 292 | What are the advantages of formik over redux form library? |
| 293 | Why do you not required to use inheritance? |
| 294 | Can I use web components in react application? |
| 295 | What is dynamic import? |
| 296 | What are loadable components? |
| 297 | What is suspense component? |
| 298 | What is route based code splitting? |
| 299 | Give an example on How to use context? |
| 300 | What is the purpose of default value in context? |
| 301 | How do you use contextType? |
| 302 | What is a consumer? |
| 303 | How do you solve performance corner cases while using context? |
| 304 | What is the purpose of forward ref in HOCs? |
| 305 | Is it ref argument available for all functions or class components? |
| 306 | Why do you need additional care for component libraries while using forward refs? |
| 307 | How to create react class components without ES6? |
| 308 | Is it possible to use react without JSX? |
| 309 | What is diffing algorithm? |
| 310 | What are the rules covered by diffing algorithm? |
| 311 | When do you need to use refs? |
| 312 | Is it prop must be named as render for render props? |
| 313 | What are the problems of using render props with pure components? |
| 314 | How do you create HOC using render props? |
| 315 | What is windowing technique? |
| 316 | How do you print falsy values in JSX? |
| 317 | What is the typical use case of portals? |
| 318 | How do you set default value for uncontrolled component? |
| 319 | What is your favorite React stack? |
| 320 | Why ReactDOM is separated from React? |
| 321 | What is the difference between Real DOM and Virtual DOM? |
| 322 | How to add Bootstrap to a react application? |
| 323 | Can you list down top websites or applications using react as front end framework? |
| 324 | Is it recommended to use CSS In JS technique in React? |
| 325 | Do I need to rewrite all my class components with hooks? |
| 326 | How to fetch data with React Hooks? |
| 327 | Is Hooks cover all use cases for classes? |
| 328 | What is the stable release for hooks support? |
| 329 | Why do we use array destructuring (square brackets notation) in useState? |
| 330 | What are the sources used for introducing hooks? |
| 331 | How do you access imperative API of web components? |
| 332 | What is formik? |
| 333 | What are typical middleware choices for handling asynchronous calls in Redux? |
| 334 | Do browsers understand JSX code? |
| 335 | Describe about data flow in react? |
| 336 | What is react scripts? |
| 337 | What are the features of create react app? |
| 338 | What is the purpose of renderToNodeStream method? |
| 339 | What is MobX? |
| 340 | What are the differences between Redux and MobX? |
| 341 | Should I learn ES6 before learning ReactJS? |
| 342 | What is Concurrent Rendering? |
| 343 | What is the difference between async mode and concurrent mode? |
| 344 | Can I use javascript urls in react16.9? |
| 345 | What is the purpose of eslint plugin for hooks? |
| 346 | What is the difference between Imperative and Declarative in React? |
| 347 | What are the benefits of using typescript with reactjs? |
| 348 | How do you make sure that user remains authenticated on page refresh while using Context API State Management? |

A
349 What are the benefits of new JSX transform?
350 How is the new JSX transform different from old transform?
351 How do you get redux scaffolding using create-react-app?
352 What are React Server components?
353 What is prop drilling?
354 What is state mutation and how to prevent it?
355 What is the difference between useState and useRef hook?
356 What is a wrapper component
357 What are the differences between useEffect and useLayoutEffect hooks
358 What are the differences between Functional and Class Components
359 Why does strict mode render twice in React?

|  | A |
|  | - |
| 349 | What are the benefits of new JSX transform? |
| 350 | How is the new JSX transform different from old transform? |
| 351 | How do you get redux scaffolding using create-react-app? |
| 352 | What are React Server components? |
| 353 | What is prop drilling? |
| 354 | What is state mutation and how to prevent it? |
| 355 | What is the difference between useState and useRef hook? |
| 356 | What is a wrapper component |
| 357 | What are the differences between useEffect and useLayoutEffect hooks |
| 358 | What are the differences between Functional and Class Components |
| 359 | Why does strict mode render twice in React? |

This is React Interview Questions Guide for beginners

Frontend Developer

Network Address
Translation (NAT) in
AWS

| Network Address
Translation (NAT) in
AWS |  |  |
| ---------------------------------------- |  |  |


|  |  |
|  |  |

Network Address Translation (NAT) is a process that converts private IP
addresses to public ones and vice versa. In AWS, NAT enables instances in
private subnets to access the internet without exposing their private IP
addresses. When an instance sends an outbound request, NAT translates its
private address to a public one so the request can traverse the internet;
when the response returns, NAT converts the public address back to the
private address of the instance.
AWS offers two NAT solutions:
NAT Gateway:
A fully managed, highly available service that automatically scales to
handle heavy traffic. It’s ideal for production environments because it
requires minimal management and delivers reliable performance.
NAT Instance:
A customizable EC2 instance configured to perform NAT. While it offers
greater flexibility for specific use cases, it requires you to manage
scaling, availability, and maintenance manually.

| Network Address Translation (NAT) is a process that converts private IP
addresses to public ones and vice versa. In AWS, NAT enables instances in
private subnets to access the internet without exposing their private IP
addresses. When an instance sends an outbound request, NAT translates its
private address to a public one so the request can traverse the internet;
when the response returns, NAT converts the public address back to the
private address of the instance.
AWS offers two NAT solutions:
NAT Gateway:
A fully managed, highly available service that automatically scales to
handle heavy traffic. It’s ideal for production environments because it
requires minimal management and delivers reliable performance.
NAT Instance:
A customizable EC2 instance configured to perform NAT. While it offers
greater flexibility for specific use cases, it requires you to manage
scaling, availability, and maintenance manually. |  |  |
| ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |  |  |


|  |  |
|  |  |

NAT Gateway
Overview: A fully managed, highly available AWS service that automatically
scales to handle large volumes of outbound traffic.
Advantages:
Minimal maintenance with automatic scaling and redundancy.
Ideal for production workloads requiring reliable, high-throughput
outbound connectivity.
Usage:
Configure your route tables to direct outbound traffic (using 0.0.0.0/0)
from private subnets to the NAT Gateway, which then sends the traffic
to the internet.

| NAT Gateway
Overview: A fully managed, highly available AWS service that automatically
scales to handle large volumes of outbound traffic.
Advantages:
Minimal maintenance with automatic scaling and redundancy.
Ideal for production workloads requiring reliable, high-throughput
outbound connectivity.
Usage:
Configure your route tables to direct outbound traffic (using 0.0.0.0/0)
from private subnets to the NAT Gateway, which then sends the traffic
to the internet. |  |  |
| ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |  |  |


|  |  |
|  |  |

NAT Instance
Overview: An EC2 instance manually configured to perform NAT functions.
Advantages:
Offers customization options, such as installing additional software or
tweaking configurations for specific needs.
Can be a cost-effective solution for low-volume or testing scenarios.
Challenges:
Requires you to manage scaling, high availability, and maintenance
yourself.
Usage:
Suitable for non-critical workloads or custom NAT implementations
where the flexibility of an EC2 instance is needed.

| NAT Instance
Overview: An EC2 instance manually configured to perform NAT functions.
Advantages:
Offers customization options, such as installing additional software or
tweaking configurations for specific needs.
Can be a cost-effective solution for low-volume or testing scenarios.
Challenges:
Requires you to manage scaling, high availability, and maintenance
yourself.
Usage:
Suitable for non-critical workloads or custom NAT implementations
where the flexibility of an EC2 instance is needed. |  |  |
| ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |  |  |


|  |  |
|  |  |

AWS Egress Traffic
Management
AWS uses NAT devices in combination with route tables to manage
outbound traffic from private subnets. Here’s how it works and why it’s
important:
Traffic Control with Route Tables
Route tables define how traffic flows out of your VPC. By setting a default
route (typically 0.0.0.0/0) that directs traffic to your NAT solution, you
ensure that all outbound, internet-bound traffic from private subnets
passes through the NAT.

| AWS Egress Traffic
Management
AWS uses NAT devices in combination with route tables to manage
outbound traffic from private subnets. Here’s how it works and why it’s
important:
Traffic Control with Route Tables
Route tables define how traffic flows out of your VPC. By setting a default
route (typically 0.0.0.0/0) that directs traffic to your NAT solution, you
ensure that all outbound, internet-bound traffic from private subnets
passes through the NAT. |  |  |
| ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |  |  |


|  |  |
|  |  |

Enhanced Security
Because the NAT device translates private IP addresses into a public IP, your
internal instances remain hidden from the public internet. This means that
while your instances can access external updates or services, they are not
directly exposed to inbound traffic.
Maintaining Functionality
With NAT handling egress traffic, your instances can securely download
software updates, reach external APIs, or access other necessary internet
resources all without compromising the security of your private network.
Choice of NAT Solution
AWS offers both NAT Gateways and NAT Instances. NAT Gateways are fully
managed and scale automatically for production workloads, while NAT
Instances provide more control and customization for specific use cases,
albeit with more management overhead.

| Enhanced Security
Because the NAT device translates private IP addresses into a public IP, your
internal instances remain hidden from the public internet. This means that
while your instances can access external updates or services, they are not
directly exposed to inbound traffic.
Maintaining Functionality
With NAT handling egress traffic, your instances can securely download
software updates, reach external APIs, or access other necessary internet
resources all without compromising the security of your private network.
Choice of NAT Solution
AWS offers both NAT Gateways and NAT Instances. NAT Gateways are fully
managed and scale automatically for production workloads, while NAT
Instances provide more control and customization for specific use cases,
albeit with more management overhead. |  |  |
| ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |  |  |


|  |  |
|  |  |

My responsibilities include developing frontends and researching UI to deliver visually appealing interfaces using React, Next.js, Tailwind CSS, GSAP, and Framer Motion. Currently, I am working on developing an AI-based product website.

Co-founder & UI/UX Designer

User Interface Designer

Web Developer

Student

Web Development and Design

Google UI/UX Design

Postman API Fundamentals Student Expert

Python Programming

Responsive Web Design

I built a restaurant website named "GoYum" inspired by "Swiggy"!  I implemented functionalities like search, filtering, Shimmer UI, and data fetching from APIs.

Restaurant Website - GoYum

Password Generator

Portfolio Website

RazorPay Clone (Responsive) using TailwindCSS

RazorPay Clone (Responsive)

Web Development Mini Project
TechBlog is a responsive blog website.

Blog Website - TechBlog

Web Development Mini Project
Wedlock is a responsive matrimony website.

Matrimony Site - Wedlock

"QR HoReCa Menu" is a UI/UX Design project created using Figma.
QR Menu is a kind of web app which appears after scanning a QR code. It is a web app made for a HoReCa ( Hotel Restaurant Cafe) menu card's but in this case it is designed for cafe which shows different categories of food items which are present in traditional menu card.

Project Overview :
The Product : QR Menu is a kind of web app which appears after scanning a QR code. It is a web app made for a HoReCa ( Hotel Restaurant Cafe) menu card's but in this case it is designed for cafe which shows different categories of food items which are present in traditional menu card.

It is designed for a cafe where QR code is placed on each table so that everyone on the table can see the menu QR menu by simply scanning the QR code individually instead of single traditional menu card.

It is useful since single menu card might take time to arrive on customers table from another table. If it arrives then questions arise what is the condition of that menu card . While in the case of QR menu card every person on the table is able to see the menu card at one time so the hotel could get more chance of getting more orders from the customers. Also it will help the HoReCa owners to change the price of the products on the fly as they want.

QR HoReCa Menu

Flower Catalogue App named “Blossom” is a UI/UX project  which is a online flower ordering app. This could help users to order flowers from florist near them & user can select florist as per their choice and convenience.

My responsibilities: Conducting interviews, paper and digital wireframing, low and high-fidelity prototyping, conducting usability studied, accounting for accessibility and iterating on designs.

Tools: Figma

Flower Catalogue App - Blossom

Foundations of User Experience (UX) Design

Start the UX Design Process: Empathize, Define, and Ideate

 Build Wireframes and Low-Fidelity Prototypes

Conduct UX Research and Test Early Concepts

Create High-Fidelity Designs and Prototypes in Figma

Python (Basics)

JavaScript Ultimate Guide

AWS Certification & Training

JavaScript Typescript Angular React Node Ionic Vue Meteor Mithril Ember BackBone Express Next 

React js | Nextjs | Frontend developer crafting interactive web experiences with UI design skills, currently exploring MERN stack development.

Ghanshyam Chaudhari

Entrepreneur | Founder & CEO at STSARC. | IEEE Chairperson SITRC

Ameya Belvalkar

Versatile Full-Stack Developer | JavaScript (React.js, Node.js, TypeScript) | Java (Spring Boot) | SQL | Cloud (AWS, Azure)

Gayatri Jawharkar

Graduate at Saint Louis University, Saint Louis

Abhijit Dengale

Anand Suryawanshi

Neha Rajbhoj

Computer Engineer | Full Stack Developer | MERN Stack Developer

Purva Dusane

Swaroop  Shinde

1x Red Hat Certified (EX180) ★ DevOps enthusiast ★ Docker ★ Ansible ★ Terraform ★ Jenkins ★ Linux ★ Kubernetes ★ Git-Github ★ Cloud Computing

Sayali Kapadnis

Jagrati Patil

Frontend developer with 6+ months of experience crafting interactive, user-friendly web experiences that seamlessly adapt across platforms and devices. Skilled in UI design, I focus on creating intuitive interfaces that deliver engaging, enjoyable experiences. Proficient in HTML, CSS, JavaScript, React, Next.js, Tailwind CSS, Node, Express, and GSAP, I’m actively advancing my skills to become a proficient MERN Stack Developer, with a strong emphasis on refining my frontend capabilities. 
I am currently seeking new opportunities, open to both full-time roles and freelance projects.

Divya

Frontend Developer

Frontend Developer

Co-founder & UI/UX Designer

User Interface Designer

Web Developer

Student

Web Development and Design

Chatbots by Divya

React Interview Guide

NAT