React Questions

ReactComponent DesignProps+1

React: Component Composition and the children Prop

Learn component composition in React. Understand how to design reusable wrapper layouts, handle dynamic slots, and prevent prop drilling using the children prop.

7 min read

React: Conditional Rendering Patterns & Pitfalls

Master conditional rendering in React. Compare logical AND (&&), ternary operators, and if/else conditions. Learn how to prevent common rendering bugs.

ReactRenderingUI Logic+1

6 min read

ReactContext APIState Management+2

React Context API Interview Questions

Master React Context API with practical state management interview examples and best practices. Learn how Context works, when to use it, performance considerations, and common React interview questions.

14 min read

ReactFormsState Management+2

Controlled vs Uncontrolled Components Interview Questions

Master React Controlled vs Uncontrolled Components interview questions with practical form handling examples. Learn how React manages form state, performance tradeoffs, refs, and best practices.

12 min read

React: How and When to Write Custom Hooks

Learn when to extract logic into custom React hooks, how hooks share state logic but not state instance, and guidelines for designing clean custom hook interfaces.

ReactHooksArchitecture+1

6 min read

ReactError HandlingLifecycles

React: How Error Boundaries Work

Understand how Error Boundaries catch rendering errors in React, when they fail to catch errors (asynchronous code, event handlers), and how fallback UIs are rendered.

7 min read

ReactReact 19Memoization+1

ReactHard

React Compiler (React 19 Auto-Memoization)

Understand the React Compiler (React Forget) in React 19. Learn how it automates memoization, the under-the-hood rules it enforces, and how it reduces user dependency on useMemo and useCallback.

8 min read

ReactReconciliationLists+1

React: What are keys and why are they needed?

Understand the importance of keys in React lists. Learn how keys assist the Virtual DOM reconciliation engine, the issues with using array indices as keys, and key best practices.

7 min read

React Lifecycle Interview Questions

Master React Lifecycle interview questions with practical examples. Learn mounting, updating, unmounting, lifecycle methods, useEffect, cleanup functions, and React rendering behavior.

ReactLifecycleHooks+2

14 min read

ReactPerformanceOptimization+2

ReactHard

React Performance Optimization Interview Questions

Master React Performance Optimization interview questions with practical examples. Learn React.memo, useMemo, useCallback, code splitting, lazy loading, virtualization, rendering optimization, and common React performance patterns.

18 min read