Frontend Questions

Here is the list of questions asked often during interviews. No need to memorise the answers to all of them instead just understand their concepts.

<aside> 💡 The best way to learn is to recall them immediately after understanding them or just explain them to someone in need.

</aside>

  1. What is React
  2. What is React lifecycle
  3. Explain Virtual DOM in React and its significance
  4. What is JSX
  5. Explain states and props
  6. What are props drilling in React
  7. What is key prop in React and it’s benefit
  8. What is CSR(client-side rendering)
  9. What is Higher Order Component in React
  10. What is React Context API and why do we need it?
  11. How to improve React application performance?
  12. How to avoid re-rendering in react component
  13. What are pure components and stateless components
  14. Explain code splitting in React
  15. What are Hooks and why they are introduced
  16. What are controlled and uncontrolled components
  17. What are the Container component and Presentational component
  18. What is Redux
  19. What is actions, reducers and store does in Redux
  20. What is SSR(server-side rendering)
  21. What are useCallback, useEffect, useMemo and useLayoutEffect
  22. what is useRef in React
  23. Explain the difference between var, let and const in javascript
  24. What is async/await in Javascript
  25. What is a PROMISE in Javascript
  26. Define indexOf and includes a method in javascript
  27. What is map(), filter() and reduce() methods in javascript
  28. Explain event loop in javascript
  29. Explain setTimeOut and setInterval
  30. Explain closures and hoisting in Javascript
  31. Difference between arrow function and functional declaration
  32. What is Next JS
  33. What is SSR, ISG and SSG?
  34. What is getInitialProps and getStaticProps
  35. Explain dynamic importing in React
  36. How to add routing in React applications
  37. How to add pagination in React application
  38. How to handle responsiveness in React application
  39. How to improve SEO of React application
  40. Explain React Fiber and its benefits
  41. What do Babel and Webpack do
  42. Why do we need to transpile React code
  43. What is the strict mode component and How to use it?
  44. What is lazy loading and how to add it
  45. What are synthetic events in react
  46. What is React Portal
  47. What is reconciliation algorithm in React
  48. What is REST API
  49. How to fetch data using API in frontend, explain axios and fetch module
  50. How to access Window object in React application