Conceptual Questions for React.js Development | Prepare for Interviews

JSX (JavaScript XML) is a syntax extension for JavaScript that allows developers to write HTML-li...

2. What is the difference between Element and Component in React?

In React, elements and components are two fundamental concepts that are often used interchangeabl...

3. What are the two main types of components in React?

In React, there are two primary categories of components: Functional Components ...

4. Explain the concept of Virtual DOM in React.

The Virtual DOM is a key concept in React that enables efficient rendering of components by minim...

5. What are state and props in React?

In React, State and Props are two fundamental concepts that hel...

6. What are synthetic events in React?

In React, Synthetic Events are a way to handle user interactions (such as clicks...

7. How do you pass data from a child component to a parent component that moves up the component tree in React?

When working with React components, it's common to need to pass data from a child component to it...

8. What were the key reasons behind the shift from class-based components to stateful functional components in React?

In recent years, the React ecosystem has undergone significant changes. One of these changes is t...

9. How do hooks work in React?

Hooks are a new feature introduced in React 16.8 that allow function components to have state and...

10. Can you describe the useEffect hook and it's purpose in React?

The useEffect hook is a built-in React feature that allows you to run side effects (...

11. When do you use Redux or Context API for State management?

State management is a crucial aspect of building scalable React applications. Two popular approac...

12. How do you fetch data with hooks in React?

React Hooks provide a way to manage state and side effects within functional components. When it ...

13. What rules should be followed while using hooks in React?

React Hooks provide a way to reuse stateful logic between components without changing the compone...

14. What is the process of reconciliation in React?

Reconciliation is a key concept in React that enables efficient updates to components and their c...

15. What is memoization in React components and how can it improve performance?

Memoization is an optimization technique used to improve performance by storing the results of ex...

16. What are React Fragments and why are they useful?

React Fragments provide a way to group multiple elements in a component without adding an extra D...

17. What are React Portals and why are they useful?

A Portal is a feature provided by the react-dom package that allows rendering childr...

18. What are Lazy Loading and Suspense in React?

Suspense and "Lazy Loading" are two related yet distinct concepts in React that aim ...

19. What are route guards and how can you implement them in React?

Route guards are a crucial aspect of routing systems, particularly in Single-Page Applications (S...

20. How do you implement internationalization (i18n) in a React application?

Internationalization (i18n) refers to the process of designing and developing applications that c...

21. What are accessibility guidelines and how can they be implemented in React?

Accessibility guidelines are a set of recommendations that ensure digital products, including web...

22. How can you prevent unnecessary re-renders in React?

React applications often involve rendering components that depend on state or props changes. Howe...

23. What are error boundaries in React and how do they work?

Error boundaries are an essential concept in React that help handle errors in a more robust way. ...

24. What are controlled and uncontrolled components in React?

Controlled and uncontrolled components are fundamental concepts in React that help manage state a...

25. How do you implement a compound component pattern in React?

The Compound Component Pattern is a design approach used in React that involves brea...

26. What is the children prop in React and how does it work?

The children prop in React refers to the child elements of a component. It's a speci...

27. What is prop drilling in React and how can it be avoided?

Prop drilling is a common issue in React applications where props are passed down from a parent c...

28. What is the purpose of the key prop in React?

The key prop is a unique identifier assigned to each element in a list of components...

29. What is React.cloneElement and how is it used?

React.cloneElement is a method that creates a new copy of an element with modified p...

30. What is the useDeferredValue hook in React and how does it improve performance?