React is a JavaScript library developed by Facebook for building user interfaces using reusable components and a virtual DOM for efficient rendering.

What are React hooks?

Hooks are functions that allow you to use state and lifecycle features in functional components. Common hooks include useState, useEffect, useContext, and useReducer.

What is the virtual DOM?

The virtual DOM is an in-memory representation of the real DOM. React uses it to determine what changes need to be made and updates only those parts in the actual DOM efficiently.

React.js Interview Questions

381. What are the tradeoffs between Webpack, Vite, Turbopack, and esbuild in React ecosystems?

382. How would you optimize React build pipelines for very large repositories?

383. What distributed caching strategies improve React build scalability?

384. How would you design scalable visual-regression testing systems for React?

385. How do screenshot-based regression systems fail at scale?

386. How would you evaluate whether React remains the right framework for an organization?

387. What signals indicate that a frontend-framework migration should be considered?

388. How would you incrementally migrate away from React in a large enterprise?

389. What organizational risks arise during frontend-framework transitions?

390. How do you balance React modernization efforts with ongoing product delivery?