https://cloudmato.com/tags/javascript/Recent content in JavaScript on cloudmato.comHugo -- gohugo.ioencloudmato.comcloudmato.comSat, 30 May 2026 17:26:46 +0530https://cloudmato.com/posts/react-interview-questions-beginner-to-expert/Sat, 30 May 2026 17:26:46 +0530cloudmato.comhttps://cloudmato.com/posts/react-interview-questions-beginner-to-expert/<p>React remains the dominant UI library in the frontend ecosystem, and interviewers at startups and FAANG companies alike use React-specific questions to measure depth of knowledge [1]. This guide walks you through the most commonly asked questions in order of difficulty—from entry-level fundamentals all the way to expert-tier architecture and React 19 internals—so you can walk into any frontend interview fully prepared.</p> <h2>Beginner: Core Concepts Every Candidate Must Know</h2> <p><strong>1. What is React, and what problem does it solve?</strong> React is a JavaScript library for building composable user interfaces maintained by Meta. It solves the problem of keeping the UI in sync with application state by tracking changes and updating only the affected parts of the DOM [2].</p>